This semi-annual shareholder report contains important information about Gateway Equity Call Premium 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

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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 investment^{Footnote Reference†}
Class A	$47	0.93%

Footnote	Description
Footnote^†	Annualized for periods less than one year (if applicable).

Expenses Paid, Amount

$ 47

Expense Ratio, Percent

0.93%

AssetsNet

$ 266,754,056

Holdings Count | Holding

257

Advisory Fees Paid, Amount

$ 554,951

InvestmentCompanyPortfolioTurnover

9.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets$266,754,056
# of Portfolio Holdings (including overnight repurchase agreements and derivatives)257
Portfolio Turnover Rate9%
Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$554,951

Holdings [Text Block]

Industry Summary

Value	Value
Other investments less than 3% of net assets^{Footnote Reference*}	46.4%
Capital Markets	3.7%
Banks	3.8%
Broadline Retail	4.2%
Financial Services	4.5%
Technology Hardware, Storage & Peripherals	6.2%
Interactive Media & Services	6.9%
Software	11.4%
Semiconductors & Semiconductor Equipment	12.9%

Footnote	Description
Footnote^*	Net of other assets less liabilities (including open written options)

Largest Holdings [Text Block]

Top Ten Holdings

NVIDIA Corp.	7.5%
Microsoft Corp.	7.2%
Apple, Inc.	6.0%
Amazon.com, Inc.	4.1%
Meta Platforms, Inc., Class A	3.3%
Broadcom, Inc.	2.6%
Alphabet, Inc., Class C	2.0%
Berkshire Hathaway, Inc., Class B	1.9%
Tesla, Inc.	1.7%
JPMorgan Chase & Co.	1.7%

Material Fund Change [Text Block]

Material Fund Changes

There were no material fund changes during the period.

C000146364

Shareholder Report [Line Items]

Fund Name

Gateway Equity Call Premium Fund

Class Name

Class C

Trading Symbol

GCPCX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about Gateway Equity Call Premium 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]

Additional Information Phone Number

(800) 225-5478

Additional Information Website

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 investment^{Footnote Reference†}
Class C	$84	1.68%

Footnote	Description
Footnote^†	Annualized for periods less than one year (if applicable).

Expenses Paid, Amount

$ 84

Expense Ratio, Percent

1.68%

AssetsNet

$ 266,754,056

Holdings Count | Holding

257

Advisory Fees Paid, Amount

$ 554,951

InvestmentCompanyPortfolioTurnover

9.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets$266,754,056
# of Portfolio Holdings (including overnight repurchase agreements and derivatives)257
Portfolio Turnover Rate9%
Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$554,951

Holdings [Text Block]

Industry Summary

Value	Value
Other investments less than 3% of net assets^{Footnote Reference*}	46.4%
Capital Markets	3.7%
Banks	3.8%
Broadline Retail	4.2%
Financial Services	4.5%
Technology Hardware, Storage & Peripherals	6.2%
Interactive Media & Services	6.9%
Software	11.4%
Semiconductors & Semiconductor Equipment	12.9%

Footnote	Description
Footnote^*	Net of other assets less liabilities (including open written options)

Largest Holdings [Text Block]

Top Ten Holdings

NVIDIA Corp.	7.5%
Microsoft Corp.	7.2%
Apple, Inc.	6.0%
Amazon.com, Inc.	4.1%
Meta Platforms, Inc., Class A	3.3%
Broadcom, Inc.	2.6%
Alphabet, Inc., Class C	2.0%
Berkshire Hathaway, Inc., Class B	1.9%
Tesla, Inc.	1.7%
JPMorgan Chase & Co.	1.7%

Material Fund Change [Text Block]

Material Fund Changes

There were no material fund changes during the period.

C000190731

Shareholder Report [Line Items]

Fund Name

Gateway Equity Call Premium Fund

Class Name

Class N

Trading Symbol

GCPNX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about Gateway Equity Call Premium 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]

Additional Information Phone Number

(800) 225-5478

Additional Information Website

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 investment^{Footnote Reference†}
Class N	$32	0.63%

Footnote	Description
Footnote^†	Annualized for periods less than one year (if applicable).

Expenses Paid, Amount

$ 32

Expense Ratio, Percent

0.63%

AssetsNet

$ 266,754,056

Holdings Count | Holding

257

Advisory Fees Paid, Amount

$ 554,951

InvestmentCompanyPortfolioTurnover

9.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets$266,754,056
# of Portfolio Holdings (including overnight repurchase agreements and derivatives)257
Portfolio Turnover Rate9%
Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$554,951

Holdings [Text Block]

Industry Summary

Value	Value
Other investments less than 3% of net assets^{Footnote Reference*}	46.4%
Capital Markets	3.7%
Banks	3.8%
Broadline Retail	4.2%
Financial Services	4.5%
Technology Hardware, Storage & Peripherals	6.2%
Interactive Media & Services	6.9%
Software	11.4%
Semiconductors & Semiconductor Equipment	12.9%

Footnote	Description
Footnote^*	Net of other assets less liabilities (including open written options)

Largest Holdings [Text Block]

Top Ten Holdings

NVIDIA Corp.	7.5%
Microsoft Corp.	7.2%
Apple, Inc.	6.0%
Amazon.com, Inc.	4.1%
Meta Platforms, Inc., Class A	3.3%
Broadcom, Inc.	2.6%
Alphabet, Inc., Class C	2.0%
Berkshire Hathaway, Inc., Class B	1.9%
Tesla, Inc.	1.7%
JPMorgan Chase & Co.	1.7%

Material Fund Change [Text Block]

Material Fund Changes

There were no material fund changes during the period.

C000146365

Shareholder Report [Line Items]

Fund Name

Gateway Equity Call Premium Fund

Class Name

Class Y

Trading Symbol

GCPYX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about Gateway Equity Call Premium 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]

Additional Information Phone Number

(800) 225-5478

Additional Information Website

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 investment^{Footnote Reference†}
Class Y	$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

$ 266,754,056

Holdings Count | Holding

257

Advisory Fees Paid, Amount

$ 554,951

InvestmentCompanyPortfolioTurnover

9.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets$266,754,056
# of Portfolio Holdings (including overnight repurchase agreements and derivatives)257
Portfolio Turnover Rate9%
Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$554,951

Holdings [Text Block]

Industry Summary

Value	Value
Other investments less than 3% of net assets^{Footnote Reference*}	46.4%
Capital Markets	3.7%
Banks	3.8%
Broadline Retail	4.2%
Financial Services	4.5%
Technology Hardware, Storage & Peripherals	6.2%
Interactive Media & Services	6.9%
Software	11.4%
Semiconductors & Semiconductor Equipment	12.9%

Footnote	Description
Footnote^*	Net of other assets less liabilities (including open written options)

Largest Holdings [Text Block]

Top Ten Holdings

NVIDIA Corp.	7.5%
Microsoft Corp.	7.2%
Apple, Inc.	6.0%
Amazon.com, Inc.	4.1%
Meta Platforms, Inc., Class A	3.3%
Broadcom, Inc.	2.6%
Alphabet, Inc., Class C	2.0%
Berkshire Hathaway, Inc., Class B	1.9%
Tesla, Inc.	1.7%
JPMorgan Chase & Co.	1.7%

Material Fund Change [Text Block]

Material Fund Changes

There were no material fund changes during the period.

C000052969

Shareholder Report [Line Items]

Fund Name

Gateway Fund

Class Name

Class A

Trading Symbol

GATEX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about Gateway 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]

Additional Information Phone Number

(800) 225-5478

Additional Information Website

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 investment^{Footnote Reference†}
Class A	$47	0.93%

Footnote	Description
Footnote^†	Annualized for periods less than one year (if applicable).

Expenses Paid, Amount

$ 47

Expense Ratio, Percent

0.93%

AssetsNet

$ 6,781,218,825

Holdings Count | Holding

205

Advisory Fees Paid, Amount

$ 18,564,142

InvestmentCompanyPortfolioTurnover

13.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets$6,781,218,825
# of Portfolio Holdings (including overnight repurchase agreements and derivatives)205
Portfolio Turnover Rate13%
Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$18,564,142

Holdings [Text Block]

Industry Summary

Value	Value
Other investments less than 3% of net assets^{Footnote Reference*}	46.6%
Pharmaceuticals	3.0%
Banks	4.2%
Broadline Retail	4.4%
Financial Services	4.4%
Technology Hardware, Storage & Peripherals	6.3%
Interactive Media & Services	7.1%
Software	11.2%
Semiconductors & Semiconductor Equipment	12.8%

Footnote	Description
Footnote^*	Net of other assets less liabilities (including open purchased and written options)

Largest Holdings [Text Block]

Top Ten Holdings

Microsoft Corp.	7.5%
NVIDIA Corp.	7.5%
Apple, Inc.	6.0%
Amazon.com, Inc.	4.3%
Meta Platforms, Inc., Class A	3.4%
Alphabet, Inc., Class C	2.9%
Broadcom, Inc.	2.6%
JPMorgan Chase & Co.	2.3%
Berkshire Hathaway, Inc., Class B	2.2%
Visa, Inc., Class A	1.9%

Material Fund Change [Text Block]

Material Fund Changes

There were no material fund changes during the period.

C000052970

Shareholder Report [Line Items]

Fund Name

Gateway Fund

Class Name

Class C

Trading Symbol

GTECX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about Gateway 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]

Additional Information Phone Number

(800) 225-5478

Additional Information Website

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 investment^{Footnote Reference†}
Class C	$85	1.70%

Footnote	Description
Footnote^†	Annualized for periods less than one year (if applicable).

Expenses Paid, Amount

$ 85

Expense Ratio, Percent

1.70%

AssetsNet

$ 6,781,218,825

Holdings Count | Holding

205

Advisory Fees Paid, Amount

$ 18,564,142

InvestmentCompanyPortfolioTurnover

13.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets$6,781,218,825
# of Portfolio Holdings (including overnight repurchase agreements and derivatives)205
Portfolio Turnover Rate13%
Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$18,564,142

Holdings [Text Block]

Industry Summary

Value	Value
Other investments less than 3% of net assets^{Footnote Reference*}	46.6%
Pharmaceuticals	3.0%
Banks	4.2%
Broadline Retail	4.4%
Financial Services	4.4%
Technology Hardware, Storage & Peripherals	6.3%
Interactive Media & Services	7.1%
Software	11.2%
Semiconductors & Semiconductor Equipment	12.8%

Footnote	Description
Footnote^*	Net of other assets less liabilities (including open purchased and written options)

Largest Holdings [Text Block]

Top Ten Holdings

Microsoft Corp.	7.5%
NVIDIA Corp.	7.5%
Apple, Inc.	6.0%
Amazon.com, Inc.	4.3%
Meta Platforms, Inc., Class A	3.4%
Alphabet, Inc., Class C	2.9%
Broadcom, Inc.	2.6%
JPMorgan Chase & Co.	2.3%
Berkshire Hathaway, Inc., Class B	2.2%
Visa, Inc., Class A	1.9%

Material Fund Change [Text Block]

Material Fund Changes

There were no material fund changes during the period.

C000190730

Shareholder Report [Line Items]

Fund Name

Gateway Fund

Class Name

Class N

Trading Symbol

GTENX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about Gateway 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]

Additional Information Phone Number

(800) 225-5478

Additional Information Website

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 investment^{Footnote Reference†}
Class N	$33	0.65%

Footnote	Description
Footnote^†	Annualized for periods less than one year (if applicable).

Expenses Paid, Amount

$ 33

Expense Ratio, Percent

0.65%

AssetsNet

$ 6,781,218,825

Holdings Count | Holding

205

Advisory Fees Paid, Amount

$ 18,564,142

InvestmentCompanyPortfolioTurnover

13.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets$6,781,218,825
# of Portfolio Holdings (including overnight repurchase agreements and derivatives)205
Portfolio Turnover Rate13%
Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$18,564,142

Holdings [Text Block]

Industry Summary

Value	Value
Other investments less than 3% of net assets^{Footnote Reference*}	46.6%
Pharmaceuticals	3.0%
Banks	4.2%
Broadline Retail	4.4%
Financial Services	4.4%
Technology Hardware, Storage & Peripherals	6.3%
Interactive Media & Services	7.1%
Software	11.2%
Semiconductors & Semiconductor Equipment	12.8%

Footnote	Description
Footnote^*	Net of other assets less liabilities (including open purchased and written options)

Largest Holdings [Text Block]

Top Ten Holdings

Microsoft Corp.	7.5%
NVIDIA Corp.	7.5%
Apple, Inc.	6.0%
Amazon.com, Inc.	4.3%
Meta Platforms, Inc., Class A	3.4%
Alphabet, Inc., Class C	2.9%
Broadcom, Inc.	2.6%
JPMorgan Chase & Co.	2.3%
Berkshire Hathaway, Inc., Class B	2.2%
Visa, Inc., Class A	1.9%

Material Fund Change [Text Block]

Material Fund Changes

There were no material fund changes during the period.

C000052971

Shareholder Report [Line Items]

Fund Name

Gateway Fund

Class Name

Class Y

Trading Symbol

GTEYX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about Gateway 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]

Additional Information Phone Number

(800) 225-5478

Additional Information Website

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 investment^{Footnote Reference†}
Class Y	$35	0.70%

Footnote	Description
Footnote^†	Annualized for periods less than one year (if applicable).

Expenses Paid, Amount

$ 35

Expense Ratio, Percent

0.70%

AssetsNet

$ 6,781,218,825

Holdings Count | Holding

205

Advisory Fees Paid, Amount

$ 18,564,142

InvestmentCompanyPortfolioTurnover

13.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets$6,781,218,825
# of Portfolio Holdings (including overnight repurchase agreements and derivatives)205
Portfolio Turnover Rate13%
Total Advisory Fees Paid (after waiver/reimbursement, if applicable)$18,564,142

Holdings [Text Block]

Industry Summary

Value	Value
Other investments less than 3% of net assets^{Footnote Reference*}	46.6%
Pharmaceuticals	3.0%
Banks	4.2%
Broadline Retail	4.4%
Financial Services	4.4%
Technology Hardware, Storage & Peripherals	6.3%
Interactive Media & Services	7.1%
Software	11.2%
Semiconductors & Semiconductor Equipment	12.8%

Footnote	Description
Footnote^*	Net of other assets less liabilities (including open purchased and written options)

Largest Holdings [Text Block]

Top Ten Holdings

Microsoft Corp.	7.5%
NVIDIA Corp.	7.5%
Apple, Inc.	6.0%
Amazon.com, Inc.	4.3%
Meta Platforms, Inc., Class A	3.4%
Alphabet, Inc., Class C	2.9%
Broadcom, Inc.	2.6%
JPMorgan Chase & Co.	2.3%
Berkshire Hathaway, Inc., Class B	2.2%
Visa, Inc., Class A	1.9%

Material Fund Change [Text Block]

Material Fund Changes

There were no material fund changes during the period.