v3.25.2
Shareholder Report
 6 Months Ended
Jun. 30, 2025
USD ($)
Holding
Shareholder Report [Line Items]  
Document Type N-CSRS
Amendment Flag false
Registrant Name Natixis Funds Trust II
Entity Central Index Key 0000052136
Entity Investment Company Type N-1A
Document Period End Date Jun. 30, 2025
C000094853  
Shareholder Report [Line Items]  
Fund Name Loomis Sayles Strategic Alpha Fund
Class Name Class A
Trading Symbol LABAX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Loomis Sayles Strategic Alpha Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class A
$50
0.98%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 50
Expense Ratio, Percent 0.98%
AssetsNet $ 842,659,068
Holdings Count | Holding 773
Advisory Fees Paid, Amount $ 1,968,056
InvestmentCompanyPortfolioTurnover 31.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$842,659,068
  • # of Portfolio Holdings (including overnight repurchase agreements and derivatives)773
  • Portfolio Turnover Rate31%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$1,968,056
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
32.8%
Short-Term Investments
4.2%
Equity-Linked Notes
3.0%
Banking
3.4%
ABS Home Equity
3.4%
Sovereigns
3.4%
Pharmaceuticals
3.8%
Cable Satellite
3.9%
Non-Agency Commercial Mortgage-Backed Securities
4.2%
Technology
5.6%
Collateralized Loan Obligations
6.1%
ABS Other
6.7%
Treasuries
19.5%
Footnote Description
Footnote*
 Net of other assets less liabilities (including open written options, swap agreement, forward foreign currency contracts, and futures contracts)

Credit QualityFootnote Reference† 

Group By Country Chart
Value
Value
Cash & equivalents
5.0
US Treasury
15.0
Not ratedFootnote Reference^
22.5
CCC
2.4
B
3.8
BB
12.2
BBB
24.5
A
9.3
AA
4.3
AAA
1.0
Footnote Description
Footnote†
 Credit ratings are by S&P Global Ratings. A credit rating is an assessment provided by a nationally recognized statistical rating organization (NRSRO) of the creditworthiness of an issuer with respect to debt obligations except for those debt obligations that are only privately rated. Ratings are measured on a scale that generally ranges from AAA (highest) to D (lowest). The credit ratings shown relate to the creditworthiness of the issuers of the underlying securities in the Fund, and not to the Fund or its shares. Credit ratings are subject to change.
Footnote^
 Not Rated category represents only those securities not rated by S&P Global Ratings. Such securities may be rated by other NRSROs not shown here.
Credit Quality Explanation [Text Block] Credit ratings are by S&P Global Ratings. A credit rating is an assessment provided by a nationally recognized statistical rating organization (NRSRO) of the creditworthiness of an issuer with respect to debt obligations except for those debt obligations that are only privately rated. Ratings are measured on a scale that generally ranges from AAA (highest) to D (lowest). The credit ratings shown relate to the creditworthiness of the issuers of the underlying securities in the Fund, and not to the Fund or its shares. Credit ratings are subject to change.
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period. 
C000094854  
Shareholder Report [Line Items]  
Fund Name Loomis Sayles Strategic Alpha Fund
Class Name Class C
Trading Symbol LABCX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Loomis Sayles Strategic Alpha Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class C
$87
1.73%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 87
Expense Ratio, Percent 1.73%
AssetsNet $ 842,659,068
Holdings Count | Holding 773
Advisory Fees Paid, Amount $ 1,968,056
InvestmentCompanyPortfolioTurnover 31.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$842,659,068
  • # of Portfolio Holdings (including overnight repurchase agreements and derivatives)773
  • Portfolio Turnover Rate31%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$1,968,056
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
32.8%
Short-Term Investments
4.2%
Equity-Linked Notes
3.0%
Banking
3.4%
ABS Home Equity
3.4%
Sovereigns
3.4%
Pharmaceuticals
3.8%
Cable Satellite
3.9%
Non-Agency Commercial Mortgage-Backed Securities
4.2%
Technology
5.6%
Collateralized Loan Obligations
6.1%
ABS Other
6.7%
Treasuries
19.5%
Footnote Description
Footnote*
 Net of other assets less liabilities (including open written options, swap agreement, forward foreign currency contracts, and futures contracts)

Credit QualityFootnote Reference† 

Group By Country Chart
Value
Value
Cash & equivalents
5.0
US Treasury
15.0
Not ratedFootnote Reference^
22.5
CCC
2.4
B
3.8
BB
12.2
BBB
24.5
A
9.3
AA
4.3
AAA
1.0
Footnote Description
Footnote†
 Credit ratings are by S&P Global Ratings. A credit rating is an assessment provided by a nationally recognized statistical rating organization (NRSRO) of the creditworthiness of an issuer with respect to debt obligations except for those debt obligations that are only privately rated. Ratings are measured on a scale that generally ranges from AAA (highest) to D (lowest). The credit ratings shown relate to the creditworthiness of the issuers of the underlying securities in the Fund, and not to the Fund or its shares. Credit ratings are subject to change.
Footnote^
 Not Rated category represents only those securities not rated by S&P Global Ratings. Such securities may be rated by other NRSROs not shown here.
Credit Quality Explanation [Text Block] Credit ratings are by S&P Global Ratings. A credit rating is an assessment provided by a nationally recognized statistical rating organization (NRSRO) of the creditworthiness of an issuer with respect to debt obligations except for those debt obligations that are only privately rated. Ratings are measured on a scale that generally ranges from AAA (highest) to D (lowest). The credit ratings shown relate to the creditworthiness of the issuers of the underlying securities in the Fund, and not to the Fund or its shares. Credit ratings are subject to change.
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period. 
C000190722  
Shareholder Report [Line Items]  
Fund Name Loomis Sayles Strategic Alpha Fund
Class Name Class N
Trading Symbol LASNX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Loomis Sayles Strategic Alpha Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class N
$34
0.68%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 34
Expense Ratio, Percent 0.68%
AssetsNet $ 842,659,068
Holdings Count | Holding 773
Advisory Fees Paid, Amount $ 1,968,056
InvestmentCompanyPortfolioTurnover 31.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$842,659,068
  • # of Portfolio Holdings (including overnight repurchase agreements and derivatives)773
  • Portfolio Turnover Rate31%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$1,968,056
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
32.8%
Short-Term Investments
4.2%
Equity-Linked Notes
3.0%
Banking
3.4%
ABS Home Equity
3.4%
Sovereigns
3.4%
Pharmaceuticals
3.8%
Cable Satellite
3.9%
Non-Agency Commercial Mortgage-Backed Securities
4.2%
Technology
5.6%
Collateralized Loan Obligations
6.1%
ABS Other
6.7%
Treasuries
19.5%
Footnote Description
Footnote*
 Net of other assets less liabilities (including open written options, swap agreement, forward foreign currency contracts, and futures contracts)

Credit QualityFootnote Reference† 

Group By Country Chart
Value
Value
Cash & equivalents
5.0
US Treasury
15.0
Not ratedFootnote Reference^
22.5
CCC
2.4
B
3.8
BB
12.2
BBB
24.5
A
9.3
AA
4.3
AAA
1.0
Footnote Description
Footnote†
 Credit ratings are by S&P Global Ratings. A credit rating is an assessment provided by a nationally recognized statistical rating organization (NRSRO) of the creditworthiness of an issuer with respect to debt obligations except for those debt obligations that are only privately rated. Ratings are measured on a scale that generally ranges from AAA (highest) to D (lowest). The credit ratings shown relate to the creditworthiness of the issuers of the underlying securities in the Fund, and not to the Fund or its shares. Credit ratings are subject to change.
Footnote^
 Not Rated category represents only those securities not rated by S&P Global Ratings. Such securities may be rated by other NRSROs not shown here.
Credit Quality Explanation [Text Block] Credit ratings are by S&P Global Ratings. A credit rating is an assessment provided by a nationally recognized statistical rating organization (NRSRO) of the creditworthiness of an issuer with respect to debt obligations except for those debt obligations that are only privately rated. Ratings are measured on a scale that generally ranges from AAA (highest) to D (lowest). The credit ratings shown relate to the creditworthiness of the issuers of the underlying securities in the Fund, and not to the Fund or its shares. Credit ratings are subject to change.
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period. 
C000094855  
Shareholder Report [Line Items]  
Fund Name Loomis Sayles Strategic Alpha Fund
Class Name Class Y
Trading Symbol LASYX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Loomis Sayles Strategic Alpha Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class Y
$37
0.73%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 37
Expense Ratio, Percent 0.73%
AssetsNet $ 842,659,068
Holdings Count | Holding 773
Advisory Fees Paid, Amount $ 1,968,056
InvestmentCompanyPortfolioTurnover 31.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$842,659,068
  • # of Portfolio Holdings (including overnight repurchase agreements and derivatives)773
  • Portfolio Turnover Rate31%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$1,968,056
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
32.8%
Short-Term Investments
4.2%
Equity-Linked Notes
3.0%
Banking
3.4%
ABS Home Equity
3.4%
Sovereigns
3.4%
Pharmaceuticals
3.8%
Cable Satellite
3.9%
Non-Agency Commercial Mortgage-Backed Securities
4.2%
Technology
5.6%
Collateralized Loan Obligations
6.1%
ABS Other
6.7%
Treasuries
19.5%
Footnote Description
Footnote*
 Net of other assets less liabilities (including open written options, swap agreement, forward foreign currency contracts, and futures contracts)

Credit QualityFootnote Reference† 

Group By Country Chart
Value
Value
Cash & equivalents
5.0
US Treasury
15.0
Not ratedFootnote Reference^
22.5
CCC
2.4
B
3.8
BB
12.2
BBB
24.5
A
9.3
AA
4.3
AAA
1.0
Footnote Description
Footnote†
 Credit ratings are by S&P Global Ratings. A credit rating is an assessment provided by a nationally recognized statistical rating organization (NRSRO) of the creditworthiness of an issuer with respect to debt obligations except for those debt obligations that are only privately rated. Ratings are measured on a scale that generally ranges from AAA (highest) to D (lowest). The credit ratings shown relate to the creditworthiness of the issuers of the underlying securities in the Fund, and not to the Fund or its shares. Credit ratings are subject to change.
Footnote^
 Not Rated category represents only those securities not rated by S&P Global Ratings. Such securities may be rated by other NRSROs not shown here.
Credit Quality Explanation [Text Block] Credit ratings are by S&P Global Ratings. A credit rating is an assessment provided by a nationally recognized statistical rating organization (NRSRO) of the creditworthiness of an issuer with respect to debt obligations except for those debt obligations that are only privately rated. Ratings are measured on a scale that generally ranges from AAA (highest) to D (lowest). The credit ratings shown relate to the creditworthiness of the issuers of the underlying securities in the Fund, and not to the Fund or its shares. Credit ratings are subject to change.
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period. 
C000021802  
Shareholder Report [Line Items]  
Fund Name Natixis Oakmark Fund
Class Name Class A
Trading Symbol NEFOX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Natixis Oakmark Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class A
$53
1.03%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 53
Expense Ratio, Percent 1.03%
AssetsNet $ 1,089,855,797
Holdings Count | Holding 56
Advisory Fees Paid, Amount $ 3,093,015
InvestmentCompanyPortfolioTurnover 28.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$1,089,855,797
  • # of Portfolio Holdings (including overnight repurchase agreements)56
  • Portfolio Turnover Rate28%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$3,093,015
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
32.6%
Short-Term Investments
3.9%
Health Care Equipment & Supplies
3.4%
Interactive Media & Services
3.7%
Health Care Providers & Services
3.8%
Consumer Finance
4.6%
Financial Services
4.7%
Media
5.0%
Insurance
5.8%
Oil, Gas & Consumable Fuels
9.2%
Banks
10.1%
Capital Markets
13.2%
Footnote Description
Footnote*
 Net of other assets less liabilities
Largest Holdings [Text Block]

Top Ten Holdings

Alphabet, Inc., Class A
3.7%
Citigroup, Inc.
3.6%
Charles Schwab Corp.
3.0%
Intercontinental Exchange, Inc.
2.7%
Phillips 66
2.6%
ConocoPhillips
2.5%
Bank of America Corp.
2.4%
Willis Towers Watson PLC
2.4%
Capital One Financial Corp.
2.4%
Airbnb, Inc., Class A
2.3%
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period. 
C000021804  
Shareholder Report [Line Items]  
Fund Name Natixis Oakmark Fund
Class Name Class C
Trading Symbol NECOX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Natixis Oakmark Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class C
$91
1.78%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 91
Expense Ratio, Percent 1.78%
AssetsNet $ 1,089,855,797
Holdings Count | Holding 56
Advisory Fees Paid, Amount $ 3,093,015
InvestmentCompanyPortfolioTurnover 28.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$1,089,855,797
  • # of Portfolio Holdings (including overnight repurchase agreements)56
  • Portfolio Turnover Rate28%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$3,093,015
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
32.6%
Short-Term Investments
3.9%
Health Care Equipment & Supplies
3.4%
Interactive Media & Services
3.7%
Health Care Providers & Services
3.8%
Consumer Finance
4.6%
Financial Services
4.7%
Media
5.0%
Insurance
5.8%
Oil, Gas & Consumable Fuels
9.2%
Banks
10.1%
Capital Markets
13.2%
Footnote Description
Footnote*
 Net of other assets less liabilities
Largest Holdings [Text Block]

Top Ten Holdings

Alphabet, Inc., Class A
3.7%
Citigroup, Inc.
3.6%
Charles Schwab Corp.
3.0%
Intercontinental Exchange, Inc.
2.7%
Phillips 66
2.6%
ConocoPhillips
2.5%
Bank of America Corp.
2.4%
Willis Towers Watson PLC
2.4%
Capital One Financial Corp.
2.4%
Airbnb, Inc., Class A
2.3%
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period. 
C000190720  
Shareholder Report [Line Items]  
Fund Name Natixis Oakmark Fund
Class Name Class N
Trading Symbol NOANX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Natixis Oakmark Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class N
$37
0.73%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 37
Expense Ratio, Percent 0.73%
AssetsNet $ 1,089,855,797
Holdings Count | Holding 56
Advisory Fees Paid, Amount $ 3,093,015
InvestmentCompanyPortfolioTurnover 28.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$1,089,855,797
  • # of Portfolio Holdings (including overnight repurchase agreements)56
  • Portfolio Turnover Rate28%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$3,093,015
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
32.6%
Short-Term Investments
3.9%
Health Care Equipment & Supplies
3.4%
Interactive Media & Services
3.7%
Health Care Providers & Services
3.8%
Consumer Finance
4.6%
Financial Services
4.7%
Media
5.0%
Insurance
5.8%
Oil, Gas & Consumable Fuels
9.2%
Banks
10.1%
Capital Markets
13.2%
Footnote Description
Footnote*
 Net of other assets less liabilities
Largest Holdings [Text Block]

Top Ten Holdings

Alphabet, Inc., Class A
3.7%
Citigroup, Inc.
3.6%
Charles Schwab Corp.
3.0%
Intercontinental Exchange, Inc.
2.7%
Phillips 66
2.6%
ConocoPhillips
2.5%
Bank of America Corp.
2.4%
Willis Towers Watson PLC
2.4%
Capital One Financial Corp.
2.4%
Airbnb, Inc., Class A
2.3%
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period. 
C000021805  
Shareholder Report [Line Items]  
Fund Name Natixis Oakmark Fund
Class Name Class Y
Trading Symbol NEOYX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Natixis Oakmark Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class Y
$40
0.78%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 40
Expense Ratio, Percent 0.78%
AssetsNet $ 1,089,855,797
Holdings Count | Holding 56
Advisory Fees Paid, Amount $ 3,093,015
InvestmentCompanyPortfolioTurnover 28.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$1,089,855,797
  • # of Portfolio Holdings (including overnight repurchase agreements)56
  • Portfolio Turnover Rate28%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$3,093,015
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
32.6%
Short-Term Investments
3.9%
Health Care Equipment & Supplies
3.4%
Interactive Media & Services
3.7%
Health Care Providers & Services
3.8%
Consumer Finance
4.6%
Financial Services
4.7%
Media
5.0%
Insurance
5.8%
Oil, Gas & Consumable Fuels
9.2%
Banks
10.1%
Capital Markets
13.2%
Footnote Description
Footnote*
 Net of other assets less liabilities
Largest Holdings [Text Block]

Top Ten Holdings

Alphabet, Inc., Class A
3.7%
Citigroup, Inc.
3.6%
Charles Schwab Corp.
3.0%
Intercontinental Exchange, Inc.
2.7%
Phillips 66
2.6%
ConocoPhillips
2.5%
Bank of America Corp.
2.4%
Willis Towers Watson PLC
2.4%
Capital One Financial Corp.
2.4%
Airbnb, Inc., Class A
2.3%
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period. 
C000069913  
Shareholder Report [Line Items]  
Fund Name Vaughan Nelson Mid Cap Fund
Class Name Class A
Trading Symbol VNVAX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Vaughan Nelson Mid Cap Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class A
$58
1.15%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 58
Expense Ratio, Percent 1.15%
AssetsNet $ 214,172,659
Holdings Count | Holding 60
Advisory Fees Paid, Amount $ 721,743
InvestmentCompanyPortfolioTurnover 96.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$214,172,659
  • # of Portfolio Holdings (including overnight repurchase agreements)60
  • Portfolio Turnover Rate96%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$721,743
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
31.6%
Professional Services
3.5%
Multi-Utilities
3.7%
Electric Utilities
3.7%
Semiconductors & Semiconductor Equipment
3.8%
Consumer Staples Distribution & Retail
4.3%
Aerospace & Defense
4.9%
Electronic Equipment, Instruments & Components
5.7%
Banks
5.9%
Capital Markets
6.7%
Specialty Retail
7.4%
Machinery
9.1%
Electrical Equipment
9.7%
Footnote Description
Footnote*
 Net of other assets less liabilities
Largest Holdings [Text Block]

Top Ten Holdings

Coherent Corp.
3.3%
Hubbell, Inc.
3.2%
Burlington Stores, Inc.
2.9%
Tradeweb Markets, Inc., Class A
2.8%
Vulcan Materials Co.
2.7%
Axon Enterprise, Inc.
2.6%
Reinsurance Group of America, Inc.
2.4%
Embraer SA, ADR
2.3%
Performance Food Group Co.
2.2%
Zions Bancorp NA
2.2%
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period. 
C000069914  
Shareholder Report [Line Items]  
Fund Name Vaughan Nelson Mid Cap Fund
Class Name Class C
Trading Symbol VNVCX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Vaughan Nelson Mid Cap Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class C
$96
1.90%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 96
Expense Ratio, Percent 1.90%
AssetsNet $ 214,172,659
Holdings Count | Holding 60
Advisory Fees Paid, Amount $ 721,743
InvestmentCompanyPortfolioTurnover 96.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$214,172,659
  • # of Portfolio Holdings (including overnight repurchase agreements)60
  • Portfolio Turnover Rate96%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$721,743
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
31.6%
Professional Services
3.5%
Multi-Utilities
3.7%
Electric Utilities
3.7%
Semiconductors & Semiconductor Equipment
3.8%
Consumer Staples Distribution & Retail
4.3%
Aerospace & Defense
4.9%
Electronic Equipment, Instruments & Components
5.7%
Banks
5.9%
Capital Markets
6.7%
Specialty Retail
7.4%
Machinery
9.1%
Electrical Equipment
9.7%
Footnote Description
Footnote*
 Net of other assets less liabilities
Largest Holdings [Text Block]

Top Ten Holdings

Coherent Corp.
3.3%
Hubbell, Inc.
3.2%
Burlington Stores, Inc.
2.9%
Tradeweb Markets, Inc., Class A
2.8%
Vulcan Materials Co.
2.7%
Axon Enterprise, Inc.
2.6%
Reinsurance Group of America, Inc.
2.4%
Embraer SA, ADR
2.3%
Performance Food Group Co.
2.2%
Zions Bancorp NA
2.2%
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period. 
C000128764  
Shareholder Report [Line Items]  
Fund Name Vaughan Nelson Mid Cap Fund
Class Name Class N
Trading Symbol VNVNX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Vaughan Nelson Mid Cap Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class N
$43
0.85%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 43
Expense Ratio, Percent 0.85%
AssetsNet $ 214,172,659
Holdings Count | Holding 60
Advisory Fees Paid, Amount $ 721,743
InvestmentCompanyPortfolioTurnover 96.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$214,172,659
  • # of Portfolio Holdings (including overnight repurchase agreements)60
  • Portfolio Turnover Rate96%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$721,743
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
31.6%
Professional Services
3.5%
Multi-Utilities
3.7%
Electric Utilities
3.7%
Semiconductors & Semiconductor Equipment
3.8%
Consumer Staples Distribution & Retail
4.3%
Aerospace & Defense
4.9%
Electronic Equipment, Instruments & Components
5.7%
Banks
5.9%
Capital Markets
6.7%
Specialty Retail
7.4%
Machinery
9.1%
Electrical Equipment
9.7%
Footnote Description
Footnote*
 Net of other assets less liabilities
Largest Holdings [Text Block]

Top Ten Holdings

Coherent Corp.
3.3%
Hubbell, Inc.
3.2%
Burlington Stores, Inc.
2.9%
Tradeweb Markets, Inc., Class A
2.8%
Vulcan Materials Co.
2.7%
Axon Enterprise, Inc.
2.6%
Reinsurance Group of America, Inc.
2.4%
Embraer SA, ADR
2.3%
Performance Food Group Co.
2.2%
Zions Bancorp NA
2.2%
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period. 
C000069915  
Shareholder Report [Line Items]  
Fund Name Vaughan Nelson Mid Cap Fund
Class Name Class Y
Trading Symbol VNVYX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Vaughan Nelson Mid Cap Fund for the period of January 1, 2025 to June 30, 2025.
Shareholder Report Annual or Semi-Annual Semi-annual Shareholder Report
Additional Information [Text Block] You can find additional information (including tax information) about the Fund at im.natixis.com/funddocuments. You can also request the information by contacting us at (800) 225-5478 or by contacting your financial intermediary directly.
Additional Information Phone Number (800) 225-5478
Additional Information Website <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">im.natixis.com/funddocuments</span>
Expenses [Text Block]

What were the fund costs for the last six months? (based on a hypothetical $10,000 investment)

Class Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference†
Class Y
$45
0.90%
Footnote Description
Footnote†
 Annualized for periods less than one year (if applicable).
Expenses Paid, Amount $ 45
Expense Ratio, Percent 0.90%
AssetsNet $ 214,172,659
Holdings Count | Holding 60
Advisory Fees Paid, Amount $ 721,743
InvestmentCompanyPortfolioTurnover 96.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

  • Total Net Assets$214,172,659
  • # of Portfolio Holdings (including overnight repurchase agreements)60
  • Portfolio Turnover Rate96%
  • Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$721,743
Holdings [Text Block]

Industry Summary

Group By Sector Chart
Value
Value
Other investments less than 3% of net assetsFootnote Reference*
31.6%
Professional Services
3.5%
Multi-Utilities
3.7%
Electric Utilities
3.7%
Semiconductors & Semiconductor Equipment
3.8%
Consumer Staples Distribution & Retail
4.3%
Aerospace & Defense
4.9%
Electronic Equipment, Instruments & Components
5.7%
Banks
5.9%
Capital Markets
6.7%
Specialty Retail
7.4%
Machinery
9.1%
Electrical Equipment
9.7%
Footnote Description
Footnote*
 Net of other assets less liabilities
Largest Holdings [Text Block]

Top Ten Holdings

Coherent Corp.
3.3%
Hubbell, Inc.
3.2%
Burlington Stores, Inc.
2.9%
Tradeweb Markets, Inc., Class A
2.8%
Vulcan Materials Co.
2.7%
Axon Enterprise, Inc.
2.6%
Reinsurance Group of America, Inc.
2.4%
Embraer SA, ADR
2.3%
Performance Food Group Co.
2.2%
Zions Bancorp NA
2.2%
Material Fund Change [Text Block]

Material Fund Changes 

There were no material fund changes during the period.