NET INCOME PER SHARE - Calculations of Basic and Diluted Net Income Per Share, Including a Reconciliation of Numerators and Denominators (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Numerator:
Net (loss) income available to Extended Stay America, Inc. common shareholders - basic	$ (12,363)	$ 53,497	$ (7,809)	$ 75,431
Income attributable to noncontrolling interests assuming conversion	(3)	(7)	(5)	(12)
Net income available to common shareholders - diluted	$ (12,366)	$ 53,490	$ (7,814)	$ 75,419
Denominator:
Weighted-average number of Extended Stay America, Inc. common shares outstanding - basic (shares)	177,551	188,450	177,771	188,399
Dilutive securities (shares)	0	363	0	296
Weighted-average number of common shares outstanding - diluted (shares)	177,551	188,813	177,771	188,695
Net (loss) income per common share - basic (dollars per share)	$ (0.07)	$ 0.28	$ (0.04)	$ 0.40
Net (loss) income per common share - diluted (dollars per share)	$ (0.07)	$ 0.28	$ (0.04)	$ 0.40
Anti-dilutive securities excluded from net loss per common share (in shares)	293	0	237	0