MAA Equity - Summary of Changes in Total Equity and its Components (Parenthetical) (Details) - Mid America Apartment Communities Inc. Shareholders Equity [Member] - $ / shares	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Equity [Line Items]
Dividends on common stock, per share	$ 1.025	$ 1.000	$ 3.075	$ 3.000
Dividends on noncontrolling interests, per unit	$ 1.025	$ 1.000	$ 3.075	$ 3.000

Per share or unit amount, after investment expense, of dividend and interest investment income (loss).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 205
-Section 50
-Paragraph 7
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25866437&loc=d3e10246-115837

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration