Annual Fund Operating Expenses - AMERICAN HIGH-INCOME MUNICIPAL BOND FUND	Sep. 30, 2026
AMERICAN HIGH-INCOME MUNICIPAL BOND FUND (Class A, Class C, Class F-1, Class F-2, Class F-3) \| Class A
Prospectus [Line Items]
Management Fees (as a percentage of Assets)	0.28%
Distribution and Service (12b-1) Fees	0.30%
Other Expenses (as a percentage of Assets):	0.09%
Expenses (as a percentage of Assets)	0.67%
AMERICAN HIGH-INCOME MUNICIPAL BOND FUND (Class A, Class C, Class F-1, Class F-2, Class F-3) \| Class C
Prospectus [Line Items]
Management Fees (as a percentage of Assets)	0.28%
Distribution and Service (12b-1) Fees	1.00%
Other Expenses (as a percentage of Assets):	0.09%
Expenses (as a percentage of Assets)	1.37%
AMERICAN HIGH-INCOME MUNICIPAL BOND FUND (Class A, Class C, Class F-1, Class F-2, Class F-3) \| Class F-1
Prospectus [Line Items]
Management Fees (as a percentage of Assets)	0.28%
Distribution and Service (12b-1) Fees	0.25%
Other Expenses (as a percentage of Assets):	0.17%
Expenses (as a percentage of Assets)	0.70%
AMERICAN HIGH-INCOME MUNICIPAL BOND FUND (Class A, Class C, Class F-1, Class F-2, Class F-3) \| Class F-2
Prospectus [Line Items]
Management Fees (as a percentage of Assets)	0.28%
Distribution and Service (12b-1) Fees	0.00%
Other Expenses (as a percentage of Assets):	0.16%
Expenses (as a percentage of Assets)	0.44%
AMERICAN HIGH-INCOME MUNICIPAL BOND FUND (Class A, Class C, Class F-1, Class F-2, Class F-3) \| Class F-3
Prospectus [Line Items]
Management Fees (as a percentage of Assets)	0.28%
Distribution and Service (12b-1) Fees	0.00%
Other Expenses (as a percentage of Assets):	0.05%
Expenses (as a percentage of Assets)	0.33%
AMERICAN HIGH-INCOME MUNICIPAL BOND FUND (Class R6) \| Class R-6
Prospectus [Line Items]
Management Fees (as a percentage of Assets)	0.28%
Distribution and Service (12b-1) Fees	0.00%
Other Expenses (as a percentage of Assets):	0.05%
Expenses (as a percentage of Assets)	0.33%

- References

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