Earnings per Share / Unit - Computation of Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Numerator:
Net income	$ 30,281	$ 19,097	$ 77,704	$ 45,959
Less:
Noncontrolling interest	2,881	309	845	(22)
Dividends on preferred shares/Preferred distributions	12,223	17,253	38,804	46,122
Redemption of participating preferred shares/units	0	0	32,215	0
Allocation to participating securities	20	12	66	0
Numerator for basic income (loss) per common shareholders/unitholders	15,157	1,523	5,774	(141)
Add back:
Dividends on participating preferred shares/units	0	5,569	0	0
Remeasurement of participating preferred shares/units	0	(8,391)	0	0
Numerator for diluted income (loss) per common share/unit	$ 15,157	$ (1,299)	$ 5,774	$ (141)
Denominator
Weighted-average common shares outstanding - basic (in shares)	296,214,509	266,767,313	292,656,914	256,768,343
Effect of dilutive securities:
Participating preferred shares/units (in shares)	0	22,385,747	0	0
Share-based compensation plan (in shares)	753,140	0	662,331	0
Weighted-average shares outstanding - diluted (in shares)	296,967,649	289,153,060	293,319,245	256,768,343
Net income (loss) attributable to common shareholders/unitholders per share/unit
Basic (in dollars per share)	$ 0.05	$ 0.01	$ 0.02	$ 0.00
Diluted (in dollars per share)	$ 0.05	$ 0.00	$ 0.02	$ 0.00
American Homes 4 Rent, L.P.
Numerator:
Net income	$ 30,281	$ 19,097	$ 77,704	$ 45,959
Less:
Noncontrolling interest	0	(31)	(259)	8
Dividends on preferred shares/Preferred distributions	12,223	17,253	38,804	46,122
Redemption of participating preferred shares/units	0	0	32,215	0
Allocation to participating securities	21	12	66	0
Numerator for basic income (loss) per common shareholders/unitholders	18,037	1,863	6,878	(171)
Add back:
Dividends on participating preferred shares/units	0	5,569	0	0
Remeasurement of participating preferred shares/units	0	(8,391)	0	0
Numerator for diluted income (loss) per common share/unit	$ 18,037	$ (959)	$ 6,878	$ (171)
Denominator
Weighted-average common units outstanding - basic (in shares)	351,564,662	322,303,138	348,007,067	312,315,728
Effect of dilutive securities:
Participating preferred shares/units (in shares)	0	22,385,747	0	0
Share-based compensation plan (in shares)	753,140	0	662,331	0
Weighted-average common units outstanding - diluted (in shares)	352,317,802	344,688,885	348,669,398	312,315,728
Net income (loss) attributable to common shareholders/unitholders per share/unit
Basic (in dollars per share)	$ 0.05	$ 0.01	$ 0.02	$ 0.00
Diluted (in dollars per share)	$ 0.05	$ 0.00	$ 0.02	$ 0.00