v3.26.1
Shareholder Report
 6 Months Ended
Mar. 31, 2026
USD ($)
Holding
Shareholder Report [Line Items]  
Document Type N-CSRS
Amendment Flag false
Registrant Name American Funds U.S. Government Money Market Fund
Entity Central Index Key 0001454975
Entity Investment Company Type N-1A
Document Period End Date Mar. 31, 2026
American Funds® U.S. Government Money Market Fund - Class A  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class A
Trading Symbol AFAXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund
 
(the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-A
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-A
Expenses [Text Block]
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class A
$
26		0.51
%
*
*Annualized.
Expenses Paid, Amount $ 26
Expense Ratio, Percent 0.51% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class C  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class C
Trading Symbol AFCXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-C
. You can also request this information by
contacting
us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-C
Expenses [Text Block]
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class C
$
30		0.60
%
*
*Annualized.
Expenses Paid, Amount $ 30
Expense Ratio, Percent 0.60% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings
157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class T  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class T
Trading Symbol TTMXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature
Expenses [Text Block]
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class T
$
18		0.36
%
*
*Annualized.
Expenses Paid, Amount $ 18
Expense Ratio, Percent 0.36% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short
-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class F-1  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class F-1
Trading Symbol AFFXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-F1
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-F1
Expenses [Text Block]
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class F-1
$
34		0.67
%
*
*Annualized.
Expenses Paid, Amount $ 34
Expense Ratio, Percent 0.67% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio
holdings
by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class F-2  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class F-2
Trading Symbol AFGXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund
 
(the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-F2
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-F2
Expenses [Text Block]
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class F-2
$
20		0.39
%
*
*Annualized.
Expenses Paid, Amount $ 20
Expense Ratio, Percent 0.39% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by as
set
type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class F-3  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class F-3
Trading Symbol USGXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-F3
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-F3
Expenses [Text Block]
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class F-3
$
16		0.31
%
*
*Annualized.
Expenses Paid, Amount $ 16
Expense Ratio, Percent 0.31% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-
term
securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class 529-A  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class 529-A
Trading Symbol AAFXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains
imp
ortant information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-529A
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-529A
Expenses [Text Block]
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class 529-A
$
28		0.56
%
*
*Annualized.
Expenses Paid, Amount $ 28
Expense Ratio, Percent 0.56% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class 529-C  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class 529-C
Trading Symbol CCFXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-529C
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-529C
Expenses [Text Block]
What were the fund costs for the last six
months
?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class 529-C
$
33		0.65
%
*
*Annualized.
Expenses Paid, Amount $ 33
Expense Ratio, Percent 0.65% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class 529-E  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class 529-E
Trading Symbol EAFXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-529E
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-529E
Expenses [Text Block]
What were the fund costs for the last six
months
?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class 529-E
$
33		0.66
%
*
*Annualized.
Expenses Paid, Amount $ 33
Expense Ratio, Percent 0.66% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in
millions
)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class 529-T  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class 529-T
Trading Symbol TSIXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature
Expenses [Text Block]
What were the fund costs for the last six months?
(
based
on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class 529-T
$
22		0.43
%
*
*Annualized.
Expenses Paid, Amount $ 22
Expense Ratio, Percent 0.43% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class 529-F-1  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class 529-F-1
Trading Symbol FARXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-529F1
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-529F1
Expenses [Text Block]
What were the fund costs
for
the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class 529-F-1
$
24		0.48
%
*
*Annualized.
Expenses Paid, Amount $ 24
Expense Ratio, Percent 0.48% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class 529-F-2  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class 529-F-2
Trading Symbol FFFXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-529F2
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-529F2
Expenses [Text Block]
What were the fund
costs
for the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class 529-F-2
$
21		0.42
%
*
*Annualized.
Expenses Paid, Amount $ 21
Expense Ratio, Percent 0.42% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class 529-F-3  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class 529-F-3
Trading Symbol FMUXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-529F3
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-529F3
Expenses [Text Block]
What were the fund costs for the last six m
onth
s?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class 529-F-3
$
18		0.36
%
*
*Annualized.
Expenses Paid, Amount $ 18
Expense Ratio, Percent 0.36% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key
fund
statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class ABLE-A  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class ABLE-A
Trading Symbol AAZXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-ABLEA
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-ABLEA
Expenses [Text Block]
What were the fund costs for the last six months?
(based on a
hypothetical
$10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class ABLE-A
$
23		0.46
%
*
*Annualized.
Expenses Paid, Amount $ 23
Expense Ratio, Percent 0.46% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio
holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class ABLE-F-2  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class ABLE-F-2
Trading Symbol ABZXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-ABLEF2
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-ABLEF2
Expenses [Text Block]
What were the fund costs for the last six months?
(
based
on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class ABLE-F-2
$
18		0.35
%
*
*Annualized.
Expenses Paid, Amount $ 18
Expense Ratio, Percent 0.35% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class R-1  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class R-1
Trading Symbol RAAXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-R1
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-R1
Expenses [Text Block]
What were the fund costs for the last six months?
(
based
on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class R-1
$
19		0.37
%
*
*Annualized.
Expenses Paid, Amount $ 19
Expense Ratio, Percent 0.37% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund
statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class R-2  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class R-2
Trading Symbol RABXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-R2
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-R2
Expenses [Text Block]
What were the fund costs
for
the last six months?
(based on a
hypothetical
$10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class R-2
$
70		1.40
%
*
*Annualized.
Expenses Paid, Amount $ 70
Expense Ratio, Percent 1.40% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class R-2E  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class R-2E
Trading Symbol RBEXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-R2E
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-R2E
Expenses [Text Block]
What were the fund costs for the last six months?
(based on a h
ypot
hetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class R-2E
$
56		1.12
%
*
*Annualized.
Expenses Paid, Amount $ 56
Expense Ratio, Percent 1.12% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio
holdings
by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class R-3  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class R-3
Trading Symbol RACXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-R3
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-R3
Expenses [Text Block]
What were the fund costs for the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class R-3
$
48		0.95
%
*
*Annualized.
Expenses Paid, Amount $ 48
Expense Ratio, Percent 0.95% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio
holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class R-4  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class R-4
Trading Symbol RADXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-R4
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-R4
Expenses [Text Block]
What were the
fund
costs for the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class R-4
$
33		0.66
%
*
*Annualized.
Expenses Paid, Amount $ 33
Expense Ratio, Percent 0.66% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class R-5E  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class R-5E
Trading Symbol RAGXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-R5E
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-R5E
Expenses [Text Block]
What were the fund costs for the last six months?
(based on a
hypoth
etical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class R-5E
$
23		0.45
%
*
*Annualized.
Expenses Paid, Amount $ 23
Expense Ratio, Percent 0.45% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
American Funds® U.S. Government Money Market Fund - Class R-5  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class R-5
Trading Symbol RAEXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-R5
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-R5
Expenses [Text Block]
What were the fund c
os
ts for the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class R-5
$
18		0.36
%
*
*Annualized.
Expenses Paid, Amount $ 18
Expense Ratio, Percent 0.36% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total
100.00
%
American Funds® U.S. Government Money Market Fund - Class R-6  
Shareholder Report [Line Items]  
Fund Name American Funds® U.S. Government Money Market Fund
Class Name Class R-6
Trading Symbol RAFXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about American Funds U.S. Government Money Market Fund (the "fund") for the period from October 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] You can find additional information about the fund at
capitalgroup.com/mutual-fund-literature-R6
. You can also request this information by contacting us at
(800) 421-4225.
Additional Information Phone Number (800) 421-4225
Additional Information Website capitalgroup.com/mutual-fund-literature-R6
Expenses [Text Block]
What were the fund costs
for
the last six months?
(based on a hypothetical $10,000 investment)
Share class
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Class R-6
$
16		0.31
%
*
*Annualized.
Expenses Paid, Amount $ 16
Expense Ratio, Percent 0.31% [1]
Net Assets $ 35,411,000,000
Holdings Count | Holding 157
Additional Fund Statistics [Text Block]
Key fund statistics
Fund net assets (in millions)
$
35,411
Total number of portfolio holdings157
Holdings [Text Block]
Portfolio holdings by asset type
 (percent of net assets)
Short-term securities:
U.S. Treasury bills44.78
%
Federal agency bills & notes37.95
%
Repurchase agreements13.13
%
Bonds, notes & other debt instruments:
U.S. Treasury bonds & notes6.37
%
Other assets less liabilities(2.23
)
%
Total100.00
%
[1] Annualized.