v3.26.1
Shareholder Report
6 Months Ended
Apr. 30, 2026
USD ($)
Holding
Shareholder Report [Line Items]  
Document Type N-CSRS
Amendment Flag false
Registrant Name COMMERCE FUNDS
Entity Central Index Key 0000926243
Entity Investment Company Type N-1A
Document Period End Date Apr. 30, 2026
Shareholder Report Annual or Semi-Annual Semi-Annual Shareholder Report
C000027719  
Shareholder Report [Line Items]  
Fund Name Commerce Growth Fund
Trading Symbol CFGRX
Annual or Semi-Annual Statement [Text Block] This Semi-Annual shareholder report contains important information about Commerce Growth Fund for the period of November 1, 2025 to April 30, 2026.
Additional Information [Text Block] You can find additional information about the Fund at www.commercefunds.com. You can also request this information by contacting us at 1-800-995-6365.
Material Fund Change Notice [Text Block] This report also describes changes to the Fund that occurred after the end of the reporting period.
Additional Information Phone Number 1-800-995-6365
Additional Information Website www.commercefunds.com
Expenses [Text Block]

What were the Fund costs for the last six months?

Semi-Annual Fund Operating Expenses

(based on a hypothetical $10,000 investment)

Table Summary
Fund
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Commerce Growth Fund
$37
0.75%Footnote Reference*
Footnote Description
Footnote*
Annualized
Expenses Paid, Amount $ 37
Expense Ratio, Percent 0.75% [1]
Material Change Date Apr. 30, 2026
AssetsNet $ 192,482,950
Holdings Count | Holding 52
Advisory Fees Paid, Amount $ 402,507
InvestmentCompanyPortfolioTurnover 14.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
FUND STATISTICS
A
Total Net Assets
$192,482,950
# of Portfolio Holdings
52
Portfolio Turnover Rate
14%
Total Advisory Fees Paid
$402,507
Holdings [Text Block]

Sector Allocation (% of Total Net Assets)

Group By Sector Chart
Table Summary
Value
Value
Other
1.0%
Energy
1.0%
Exchange Traded Fund
1.3%
Consumer Staples
3.1%
Industrials
4.6%
Financials
5.5%
Health Care
5.5%
Communication Services
13.5%
Consumer Discretionary
14.3%
Information Technology
50.0%
Largest Holdings [Text Block]

Top Ten Issuers (% of Total Net Assets) 

Table Summary
NVIDIA Corp.
13.5%
Apple, Inc.
11.0%
Microsoft Corp.
9.4%
Alphabet, Inc., Class A
7.0%
Broadcom, Inc.
5.3%
Amazon.com, Inc.
5.1%
Meta Platforms, Inc., Class A
3.1%
Tesla, Inc.
2.9%
Eli Lilly & Co.
2.0%
Visa, Inc., Class A
1.6%
Material Fund Change Expenses [Text Block] At its May 14, 2026 meeting, the Board of Trustees of The Commerce Funds approved the permanent reduction of the Fund's contractual fee rate, as well as a new contractual expense limitation for the Fund. Effective August 1, 2026, under the new contractual fee rate, the Fund's management fee, calculated as a percentage of the Fund's average daily net assets, will be reduced to 0.30%, and the Fund's contractual expense limitation will be reduced to 0.70%.
Updated Prospectus Phone Number 1-800-995-6365
Updated Prospectus Email Address <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;">commercefunds@commercebank.com</span>
Updated Prospectus Web Address https://www.commercefunds.com/literature-and-resources/prospectus-and-guide
C000027721  
Shareholder Report [Line Items]  
Fund Name Commerce Value Fund
Trading Symbol CFVLX
Annual or Semi-Annual Statement [Text Block] This Semi-Annual shareholder report contains important information about Commerce Value Fund for the period of November 1, 2025 to April 30, 2026.
Additional Information [Text Block] You can find additional information about the Fund at www.commercefunds.com. You can also request this information by contacting us at 1-800-995-6365.
Material Fund Change Notice [Text Block] This report also describes changes to the Fund that occurred after the end of the reporting period.
Additional Information Phone Number 1-800-995-6365
Additional Information Website www.commercefunds.com
Expenses [Text Block]

What were the Fund costs for the last six months?

Semi-Annual Fund Operating Expenses

(based on a hypothetical $10,000 investment)

Table Summary
Fund
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Commerce Value Fund
$36
0.69%Footnote Reference*
Footnote Description
Footnote*
Annualized
Expenses Paid, Amount $ 36
Expense Ratio, Percent 0.69% [2]
Material Change Date Apr. 30, 2026
AssetsNet $ 229,911,519
Holdings Count | Holding 58
Advisory Fees Paid, Amount $ 353,323
InvestmentCompanyPortfolioTurnover 19.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
FUND STATISTICS
A
Total Net Assets
$229,911,519
# of Portfolio Holdings
58
Portfolio Turnover Rate
19%
Total Advisory Fees Paid
$353,323
Holdings [Text Block]

Sector Allocation (% of Total Net Assets)

Group By Sector Chart
Table Summary
Value
Value
Other
8.4%
Utilities
4.4%
Consumer Discretionary
6.7%
Energy
7.3%
Consumer Staples
7.9%
Communication Services
9.1%
Health Care
10.6%
Industrials
12.1%
Information Technology
13.8%
Financials
19.6%
Largest Holdings [Text Block]

Top Ten Issuers (% of Total Net Assets) 

Table Summary
Alphabet, Inc., Class A
3.6%
Texas Instruments, Inc.
2.8%
JPMorgan Chase & Co.
2.4%
Eaton Corp. PLC
2.4%
Morgan Stanley
2.3%
Cisco Systems, Inc.
2.3%
Berkshire Hathaway, Inc., Class B
2.2%
Blackrock, Inc.
2.2%
Bank of America Corp.
2.1%
Prologis, Inc.
2.0%
Material Fund Change Expenses [Text Block] At its May 14, 2026 meeting, the Board of Trustees of The Commerce Funds approved the permanent reduction of the Fund's contractual fee rate. Effective August 1, 2026, under the new contractual fee rate, the Fund's management fee, calculated as a percentage of the Fund's average daily net assets, will be reduced to 0.25%.
Updated Prospectus Phone Number 1-800-995-6365
Updated Prospectus Email Address <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;">commercefunds@commercebank.com</span>
Updated Prospectus Web Address https://www.commercefunds.com/literature-and-resources/prospectus-and-guide
C000027723  
Shareholder Report [Line Items]  
Fund Name Commerce MidCap Growth Fund
Trading Symbol CFAGX
Annual or Semi-Annual Statement [Text Block] This Semi-Annual shareholder report contains important information about Commerce MidCap Growth Fund for the period of November 1, 2025 to April 30, 2026.
Additional Information [Text Block] You can find additional information about the Fund at www.commercefunds.com. You can also request this information by contacting us at 1-800-995-6365.
Material Fund Change Notice [Text Block] This report also describes changes to the Fund that occurred after the end of the reporting period.
Additional Information Phone Number 1-800-995-6365
Additional Information Website www.commercefunds.com
Expenses [Text Block]

What were the Fund costs for the last six months?

Semi-Annual Fund Operating Expenses

(based on a hypothetical $10,000 investment)

Table Summary
Fund
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Commerce MidCap Growth Fund
$44
0.89%Footnote Reference*
Footnote Description
Footnote*
Annualized
Expenses Paid, Amount $ 44
Expense Ratio, Percent 0.89% [3]
Material Change Date Apr. 30, 2026
AssetsNet $ 129,701,292
Holdings Count | Holding 76
Advisory Fees Paid, Amount $ 362,430
InvestmentCompanyPortfolioTurnover 28.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
FUND STATISTICS
A
Total Net Assets
$129,701,292
# of Portfolio Holdings
76
Portfolio Turnover Rate
28%
Total Advisory Fees Paid
$362,430
Holdings [Text Block]

Sector Allocation (% of Total Net Assets)

Group By Sector Chart
Table Summary
Value
Value
Other
3.6%
Exchange Traded Fund
2.8%
Utilities
2.8%
Energy
2.9%
Communication Services
5.2%
Financials
6.7%
Health Care
13.5%
Information Technology
16.8%
Consumer Discretionary
19.1%
Industrials
26.0%
Largest Holdings [Text Block]

Top Ten Issuers (% of Total Net Assets) 

Table Summary
Vertiv Holdings Co., Class A
4.0%
Howmet Aerospace, Inc.
3.0%
iShares Russell Mid-Cap Growth ETF
2.8%
Quanta Services, Inc.
2.5%
Monolithic Power Systems, Inc.
2.4%
Hilton Worldwide Holdings, Inc.
2.3%
Royal Caribbean Cruises Ltd.
2.1%
Comfort Systems USA, Inc.
2.0%
Cloudflare, Inc., Class A
1.9%
Vistra Corp.
1.7%
Material Fund Change Expenses [Text Block] At its May 14, 2026 meeting, the Board of Trustees of The Commerce Funds approved the permanent reduction of the Fund's contractual fee rate. Effective August 1, 2026, under the new contractual fee rate, the Fund's management fee, calculated as a percentage of the Fund's average daily net assets, will be reduced to 0.30%.
Updated Prospectus Phone Number 1-800-995-6365
Updated Prospectus Email Address <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;">commercefunds@commercebank.com</span>
Updated Prospectus Web Address https://www.commercefunds.com/literature-and-resources/prospectus-and-guide
C000246257  
Shareholder Report [Line Items]  
Fund Name Commerce MidCap Value Fund
Trading Symbol CFMVX
Annual or Semi-Annual Statement [Text Block] This Semi-Annual shareholder report contains important information about Commerce MidCap Value Fund for the period of November 1, 2025 to April 30, 2026.
Additional Information [Text Block] You can find additional information about the Fund at www.commercefunds.com. You can also request this information by contacting us at 1-800-995-6365.
Material Fund Change Notice [Text Block] This report also describes changes to the Fund that occurred after the end of the reporting period.
Additional Information Phone Number 1-800-995-6365
Additional Information Website www.commercefunds.com
Expenses [Text Block]

What were the Fund costs for the last six months?

Semi-Annual Fund Operating Expenses

(based on a hypothetical $10,000 investment)

Table Summary
Fund
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference**
Commerce MidCap Value Fund
$37
0.70%Footnote Reference*
Footnote Description
Footnote*
Annualized
Footnote**
Reflects fee waiver and/or expense reimbursements, without which expenses would have been higher.
Expenses Paid, Amount $ 37
Expense Ratio, Percent 0.70% [4]
Material Change Date Apr. 30, 2026
AssetsNet $ 38,981,055
Holdings Count | Holding 81
Advisory Fees Paid, Amount $ 31,780
InvestmentCompanyPortfolioTurnover 28.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
FUND STATISTICS
A
Total Net Assets
$38,981,055
# of Portfolio Holdings
81
Portfolio Turnover Rate
28%
Total Advisory Fees Paid
$31,780
Holdings [Text Block]

Sector Allocation (% of Total Net Assets)

Group By Sector Chart
Table Summary
Value
Value
Other
13.7%
Materials
4.8%
Health Care
6.5%
Energy
6.7%
Utilities
6.8%
Consumer Discretionary
8.0%
Real Estate
8.6%
Information Technology
13.7%
Financials
15.0%
Industrials
17.2%
Largest Holdings [Text Block]

Top Ten Issuers (% of Total Net Assets) 

Table Summary
iShares Russell Mid-Cap Value ETF
4.0%
Monolithic Power Systems, Inc.
1.7%
State Street Institutional US Government Money Market Fund, Premier Class
1.7%
Microchip Technology, Inc.
1.7%
TD SYNNEX Corp.
1.6%
Skyworks Solutions, Inc.
1.5%
Cummins, Inc.
1.4%
State Street Corp.
1.4%
Eaton Corp. PLC
1.3%
Littelfuse, Inc.
1.3%
Material Fund Change Expenses [Text Block] At its May 14, 2026 meeting, the Board of Trustees of The Commerce Funds approved the permanent reduction of the Fund's contractual fee rate. Effective August 1, 2026, under the new contractual fee rate, the Fund's management fee, calculated as a percentage of the Fund's average daily net assets, will be reduced to 0.30%.
Updated Prospectus Phone Number 1-800-995-6365
Updated Prospectus Email Address <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;">commercefunds@commercebank.com</span>
Updated Prospectus Web Address https://www.commercefunds.com/literature-and-resources/prospectus-and-guide
C000027729  
Shareholder Report [Line Items]  
Fund Name Commerce Bond Fund
Trading Symbol CFBNX
Annual or Semi-Annual Statement [Text Block] This Semi-Annual shareholder report contains important information about Commerce Bond Fund for the period of November 1, 2025 to April 30, 2026.
Additional Information [Text Block] You can find additional information about the Fund at www.commercefunds.com. You can also request this information by contacting us at 1-800-995-6365.
Material Fund Change Notice [Text Block] This report also describes changes to the Fund that occurred after the end of the reporting period.
Additional Information Phone Number 1-800-995-6365
Additional Information Website www.commercefunds.com
Expenses [Text Block]

What were the Fund costs for the last six months?

Semi-Annual Fund Operating Expenses

(based on a hypothetical $10,000 investment)

Table Summary
Fund
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Commerce Bond Fund
$31
0.63%Footnote Reference*
Footnote Description
Footnote*
Annualized
Expenses Paid, Amount $ 31
Expense Ratio, Percent 0.63% [5]
Material Change Date Apr. 30, 2026
AssetsNet $ 1,226,915,792
Holdings Count | Holding 461
Advisory Fees Paid, Amount $ 2,188,059
InvestmentCompanyPortfolioTurnover 5.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
FUND STATISTICS
A
Total Net Assets
$1,226,915,792
# of Portfolio Holdings
461
Portfolio Turnover Rate
5%
Total Advisory Fees Paid
$2,188,059
Holdings [Text Block]

Types of Security Allocation (% of Total Net Assets)

Group By Sector Chart
Table Summary
Value
Value
U.S. Government Agency Obligations
0.2%
Investment Company
1.0%
Municipal Bond Obligations
6.1%
Asset-Backed Securities
9.8%
U.S. Treasury Obligations
18.7%
Mortgage-Backed Obligations
27.9%
Corporate Obligations
35.8%

Credit Rating (% of Total Net Assets)Footnote Reference*

Table Summary
AAA
11.2%
AA
11.5%
A
21.4%
BBB
14.1%
CCC
0.2%
U.S. Govt.
39.1%
Non-Rated
2.0%
Footnote Description
Footnote*
For financial reporting purposes, credit quality ratings shown above reflect the highest rating assigned by either S&P Global Ratings or Moody’s Investors Service, Inc. if ratings differ. These rating agencies are independent, nationally recognized statistical rating organizations and are widely used. Investment grade ratings are credit ratings of BBB/Baa or higher. Below investment grade ratings are credit ratings of BB/Ba or lower. Investments designated Non-Rated or N/R are not rated by either rating agency. Unrated investments do not necessarily indicate low credit quality. Credit quality ratings are subject to change.
Credit Ratings Selection [Text Block] For financial reporting purposes, credit quality ratings shown above reflect the highest rating assigned by either S&P Global Ratings or Moody’s Investors Service, Inc. if ratings differ. These rating agencies are independent, nationally recognized statistical rating organizations and are widely used. Investment grade ratings are credit ratings of BBB/Baa or higher. Below investment grade ratings are credit ratings of BB/Ba or lower. Investments designated Non-Rated or N/R are not rated by either rating agency. Unrated investments do not necessarily indicate low credit quality. Credit quality ratings are subject to change.
Material Fund Change Expenses [Text Block] At its May 14, 2026 meeting, the Board of Trustees of The Commerce Funds approved the permanent reduction of the Fund's contractual fee rate, as well as a new contractual expense limitation for the Fund. Effective August 1, 2026, under the new contractual fee rate, the Fund's management fee, calculated as a percentage of the Fund's average daily net assets, will be reduced to 0.13%, and the Fund's contractual expense limitation will be reduced to 0.45%.
Updated Prospectus Phone Number 1-800-995-6365
Updated Prospectus Email Address <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;">commercefunds@commercebank.com</span>
Updated Prospectus Web Address https://www.commercefunds.com/literature-and-resources/prospectus-and-guide
C000027731  
Shareholder Report [Line Items]  
Fund Name Commerce Short-Term Government Fund
Trading Symbol CFSTX
Annual or Semi-Annual Statement [Text Block] This Semi-Annual shareholder report contains important information about Commerce Short-Term Government Fund for the period of November 1, 2025 to April 30, 2026.
Additional Information [Text Block] You can find additional information about the Fund at www.commercefunds.com. You can also request this information by contacting us at 1-800-995-6365.
Material Fund Change Notice [Text Block] This report also describes changes to the Fund that occurred after the end of the reporting period.
Additional Information Phone Number 1-800-995-6365
Additional Information Website www.commercefunds.com
Expenses [Text Block]

What were the Fund costs for the last six months?

Semi-Annual Fund Operating Expenses

(based on a hypothetical $10,000 investment)

Table Summary
Fund
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference**
Commerce Short-Term Government Fund
$34
0.68%Footnote Reference*
Footnote Description
Footnote*
Annualized
Footnote**
Reflects fee waiver and/or expense reimbursements, without which expenses would have been higher.
Expenses Paid, Amount $ 34
Expense Ratio, Percent 0.68% [6]
Material Change Date Apr. 30, 2026
AssetsNet $ 27,971,279
Holdings Count | Holding 113
Advisory Fees Paid, Amount $ 0
InvestmentCompanyPortfolioTurnover 6.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
FUND STATISTICS
A
Total Net Assets
$27,971,279
# of Portfolio Holdings
113
Portfolio Turnover Rate
6%
Total Advisory Fees Paid
$0
Holdings [Text Block]

Types of Security Allocation (% of Total Net Assets)

Group By Sector Chart
Table Summary
Value
Value
Asset-Backed Securities
0.9%
U.S. Government Agency Obligations
1.8%
Investment Company
8.4%
Mortgage-Backed Obligations
42.7%
U.S. Treasury Obligations
46.2%

Credit Rating (% of Total Net Assets)Footnote Reference*

Table Summary
AAA
12.9%
AA
2.3%
BB
0.6%
U.S. Govt.
82.9%
Non-Rated
1.3%
Footnote Description
Footnote*
For financial reporting purposes, credit quality ratings shown above reflect the highest rating assigned by either S&P Global Ratings or Moody’s Investors Service, Inc. if ratings differ. These rating agencies are independent, nationally recognized statistical rating organizations and are widely used. Investment grade ratings are credit ratings of BBB/Baa or higher. Below investment grade ratings are credit ratings of BB/Ba or lower. Investments designated Non-Rated or N/R are not rated by either rating agency. Unrated investments do not necessarily indicate low credit quality. Credit quality ratings are subject to change.
Credit Ratings Selection [Text Block] For financial reporting purposes, credit quality ratings shown above reflect the highest rating assigned by either S&P Global Ratings or Moody’s Investors Service, Inc. if ratings differ. These rating agencies are independent, nationally recognized statistical rating organizations and are widely used. Investment grade ratings are credit ratings of BBB/Baa or higher. Below investment grade ratings are credit ratings of BB/Ba or lower. Investments designated Non-Rated or N/R are not rated by either rating agency. Unrated investments do not necessarily indicate low credit quality. Credit quality ratings are subject to change.
Material Fund Change Objectives [Text Block]

At its May 14, 2026 meeting, the Board of Trustees of The Commerce Funds approved a plan to liquidate and terminate the Fund (the "Liquidation"). The Liquidation is anticipated to occur on or about August 31, 2026.

Updated Prospectus Phone Number 1-800-995-6365
Updated Prospectus Email Address <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;">commercefunds@commercebank.com</span>
Updated Prospectus Web Address https://www.commercefunds.com/literature-and-resources/prospectus-and-guide
C000027733  
Shareholder Report [Line Items]  
Fund Name Commerce National Tax-Free Intermediate Bond Fund
Trading Symbol CFNLX
Annual or Semi-Annual Statement [Text Block] This Semi-Annual shareholder report contains important information about Commerce National Tax-Free Intermediate Bond Fund for the period of November 1, 2025 to April 30, 2026.
Additional Information [Text Block] You can find additional information about the Fund at www.commercefunds.com. You can also request this information by contacting us at 1-800-995-6365.
Material Fund Change Notice [Text Block] This report also describes changes to the Fund that occurred after the end of the reporting period.
Additional Information Phone Number 1-800-995-6365
Additional Information Website www.commercefunds.com
Expenses [Text Block]

What were the Fund costs for the last six months?

Semi-Annual Fund Operating Expenses

(based on a hypothetical $10,000 investment)

Table Summary
Fund
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Commerce National Tax-Free Intermediate Bond Fund
$31
0.62%Footnote Reference*
Footnote Description
Footnote*
Annualized
Expenses Paid, Amount $ 31
Expense Ratio, Percent 0.62% [7]
Material Change Date Apr. 30, 2026
AssetsNet $ 349,540,343
Holdings Count | Holding 352
Advisory Fees Paid, Amount $ 610,015
InvestmentCompanyPortfolioTurnover 10.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
FUND STATISTICS
A
Total Net Assets
$349,540,343
# of Portfolio Holdings
352
Portfolio Turnover Rate
10%
Total Advisory Fees Paid
$610,015
Holdings [Text Block]

Sector Allocation (% of Total Net Assets)

Group By Sector Chart
Table Summary
Value
Value
Other
6.2%
Industrial Development Revenue/Pollution Control Revenue
3.4%
Student
4.9%
Higher Education
5.6%
Single Family Housing
6.4%
Lease
9.1%
Transportation
10.6%
Hospital
13.3%
Limited Tax
16.0%
General Obligations
24.2%

Credit Rating (% of Total Net Assets)Footnote Reference*

Table Summary
AAA
3.3%
AA
61.7%
A
30.8%
BBB
0.5%
Non-Rated
3.5%
Footnote Description
Footnote*
For financial reporting purposes, credit quality ratings shown above reflect the highest rating assigned by either S&P Global Ratings or Moody’s Investors Service, Inc. if ratings differ. These rating agencies are independent, nationally recognized statistical rating organizations and are widely used. Investment grade ratings are credit ratings of BBB/Baa or higher. Below investment grade ratings are credit ratings of BB/Ba or lower. Investments designated Non-Rated or N/R are not rated by either rating agency. Unrated investments do not necessarily indicate low credit quality. Credit quality ratings are subject to change.
Credit Ratings Selection [Text Block] For financial reporting purposes, credit quality ratings shown above reflect the highest rating assigned by either S&P Global Ratings or Moody’s Investors Service, Inc. if ratings differ. These rating agencies are independent, nationally recognized statistical rating organizations and are widely used. Investment grade ratings are credit ratings of BBB/Baa or higher. Below investment grade ratings are credit ratings of BB/Ba or lower. Investments designated Non-Rated or N/R are not rated by either rating agency. Unrated investments do not necessarily indicate low credit quality. Credit quality ratings are subject to change.
Material Fund Change Expenses [Text Block] At its May 14, 2026 meeting, the Board of Trustees of The Commerce Funds approved the permanent reduction of the Fund's contractual fee rate. Effective August 1, 2026, under the new contractual fee rate, the Fund's management fee, calculated as a percentage of the Fund's average daily net assets, will be reduced to 0.30%.
Updated Prospectus Phone Number 1-800-995-6365
Updated Prospectus Email Address <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;">commercefunds@commercebank.com</span>
Updated Prospectus Web Address https://www.commercefunds.com/literature-and-resources/prospectus-and-guide
C000027715  
Shareholder Report [Line Items]  
Fund Name Commerce Missouri Tax-Free Intermediate Bond Fund
Trading Symbol CFMOX
Annual or Semi-Annual Statement [Text Block] This Semi-Annual shareholder report contains important information about Commerce Missouri Tax-Free Intermediate Bond Fund for the period of November 1, 2025 to April 30, 2026.
Additional Information [Text Block] You can find additional information about the Fund at www.commercefunds.com. You can also request this information by contacting us at 1-800-995-6365.
Material Fund Change Notice [Text Block] This report also describes changes to the Fund that occurred after the end of the reporting period.
Additional Information Phone Number 1-800-995-6365
Additional Information Website www.commercefunds.com
Expenses [Text Block]

What were the Fund costs for the last six months?

Semi-Annual Fund Operating Expenses

(based on a hypothetical $10,000 investment)

Table Summary
Fund
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Commerce Missouri Tax-Free Intermediate Bond Fund
$34
0.69%Footnote Reference*
Footnote Description
Footnote*
Annualized
Expenses Paid, Amount $ 34
Expense Ratio, Percent 0.69% [8]
Material Change Date Apr. 30, 2026
AssetsNet $ 218,876,190
Holdings Count | Holding 208
Advisory Fees Paid, Amount $ 459,042
InvestmentCompanyPortfolioTurnover 8.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
FUND STATISTICS
A
Total Net Assets
$218,876,190
# of Portfolio Holdings
208
Portfolio Turnover Rate
8%
Total Advisory Fees Paid
$459,042
Holdings [Text Block]

Sector Allocation (% of Total Net Assets)

Group By Sector Chart
Table Summary
Value
Value
Other
1.1%
Investment Company
1.8%
Power
2.1%
Higher Education
3.4%
Single Family Housing
4.8%
Limited Tax
5.1%
Transportation
6.3%
Hospital
13.8%
General Obligations
25.9%
Lease
34.9%

Credit Rating (% of Total Net Assets)Footnote Reference*

Table Summary
AAA
0.1%
AA
55.8%
A
36.6%
BBB
3.4%
Non-Rated
3.3%
Footnote Description
Footnote*
For financial reporting purposes, credit quality ratings shown above reflect the highest rating assigned by either S&P Global Ratings or Moody’s Investors Service, Inc. if ratings differ. These rating agencies are independent, nationally recognized statistical rating organizations and are widely used. Investment grade ratings are credit ratings of BBB/Baa or higher. Below investment grade ratings are credit ratings of BB/Ba or lower. Investments designated Non-Rated or N/R are not rated by either rating agency. Unrated investments do not necessarily indicate low credit quality. Credit quality ratings are subject to change.
Credit Ratings Selection [Text Block] For financial reporting purposes, credit quality ratings shown above reflect the highest rating assigned by either S&P Global Ratings or Moody’s Investors Service, Inc. if ratings differ. These rating agencies are independent, nationally recognized statistical rating organizations and are widely used. Investment grade ratings are credit ratings of BBB/Baa or higher. Below investment grade ratings are credit ratings of BB/Ba or lower. Investments designated Non-Rated or N/R are not rated by either rating agency. Unrated investments do not necessarily indicate low credit quality. Credit quality ratings are subject to change.
Material Fund Change Expenses [Text Block] At its May 14, 2026 meeting, the Board of Trustees of The Commerce Funds approved the permanent reduction of the Fund's contractual fee rate. Effective August 1, 2026, under the new contractual fee rate, the Fund's management fee, calculated as a percentage of the Fund's average daily net assets, will be reduced to 0.30%.
Updated Prospectus Phone Number 1-800-995-6365
Updated Prospectus Email Address <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;">commercefunds@commercebank.com</span>
Updated Prospectus Web Address https://www.commercefunds.com/literature-and-resources/prospectus-and-guide
C000027717  
Shareholder Report [Line Items]  
Fund Name Commerce Kansas Tax-Free Intermediate Bond Fund
Trading Symbol KTXIX
Annual or Semi-Annual Statement [Text Block] This Semi-Annual shareholder report contains important information about Commerce Kansas Tax-Free Intermediate Bond Fund for the period of November 1, 2025 to April 30, 2026.
Additional Information [Text Block] You can find additional information about the Fund at www.commercefunds.com. You can also request this information by contacting us at 1-800-995-6365.
Material Fund Change Notice [Text Block] This report also describes changes to the Fund that occurred after the end of the reporting period.
Additional Information Phone Number 1-800-995-6365
Additional Information Website www.commercefunds.com
Expenses [Text Block]

What were the Fund costs for the last six months?

Semi-Annual Fund Operating Expenses

(based on a hypothetical $10,000 investment)

Table Summary
Fund
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investmentFootnote Reference**
Commerce Kansas Tax-Free Intermediate Bond Fund
$35
0.70%Footnote Reference*
Footnote Description
Footnote*
Annualized
Footnote**
Reflects fee waiver and/or expense reimbursements, without which expenses would have been higher.
Expenses Paid, Amount $ 35
Expense Ratio, Percent 0.70% [9]
Material Change Date Apr. 30, 2026
AssetsNet $ 101,177,343
Holdings Count | Holding 106
Advisory Fees Paid, Amount $ 173,796
InvestmentCompanyPortfolioTurnover 12.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics

Table Summary
FUND STATISTICS
A
Total Net Assets
$101,177,343
# of Portfolio Holdings
106
Portfolio Turnover Rate
12%
Total Advisory Fees Paid
$173,796
Holdings [Text Block]

Sector Allocation (% of Total Net Assets)

Group By Sector Chart
Table Summary
Value
Value
Transportation
1.3%
Power
2.0%
Multi Family Housing
2.0%
Higher Education
3.8%
Investment Company
4.1%
Water/Sewer
4.9%
Hospital
6.8%
Lease
9.7%
Limited Tax
10.9%
General Obligations
53.8%

Credit Rating (% of Total Net Assets)Footnote Reference*

Table Summary
AAA
7.4%
AA
70.0%
A
13.5%
BBB
3.1%
Non-Rated
5.4%
Footnote Description
Footnote*
For financial reporting purposes, credit quality ratings shown above reflect the highest rating assigned by either S&P Global Ratings or Moody’s Investors Service, Inc. if ratings differ. These rating agencies are independent, nationally recognized statistical rating organizations and are widely used. Investment grade ratings are credit ratings of BBB/Baa or higher. Below investment grade ratings are credit ratings of BB/Ba or lower. Investments designated Non-Rated or N/R are not rated by either rating agency. Unrated investments do not necessarily indicate low credit quality. Credit quality ratings are subject to change.
Credit Ratings Selection [Text Block] For financial reporting purposes, credit quality ratings shown above reflect the highest rating assigned by either S&P Global Ratings or Moody’s Investors Service, Inc. if ratings differ. These rating agencies are independent, nationally recognized statistical rating organizations and are widely used. Investment grade ratings are credit ratings of BBB/Baa or higher. Below investment grade ratings are credit ratings of BB/Ba or lower. Investments designated Non-Rated or N/R are not rated by either rating agency. Unrated investments do not necessarily indicate low credit quality. Credit quality ratings are subject to change.
Material Fund Change Expenses [Text Block] At its May 14, 2026 meeting, the Board of Trustees of The Commerce Funds approved the permanent reduction of the Fund's contractual fee rate. Effective August 1, 2026, under the new contractual fee rate, the Fund's management fee, calculated as a percentage of the Fund's average daily net assets, will be reduced to 0.30%.
Updated Prospectus Phone Number 1-800-995-6365
Updated Prospectus Email Address <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;">commercefunds@commercebank.com</span>
Updated Prospectus Web Address https://www.commercefunds.com/literature-and-resources/prospectus-and-guide
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