Earnings Per Share (Details) - 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
Earnings Per Share [Abstract]
Numerator for basic and diluted earnings per share - net income (loss) attributable to common stockholders		$ 179,246	$ 137,762	$ 489,530	$ 418,232
Adjustment for net income (loss) attributable to OP units		(1,366)	35	(2,754)	88
Numerator for diluted earnings per share		$ 177,880	$ 137,797	$ 486,776	$ 418,320
Denominator for basic earnings per share - weighted average shares (in shares)		417,084	404,607	413,696	398,073
Effect of dilutive securities:
Employee stock options (in shares)		0	0	0	1
Non-vested restricted shares (in shares)		619	955	661	911
Redeemable op units (in shares)		1,396	1,096	1,396	1,096
Employee stock purchase program (in shares)		22	15	22	15
Dilutive potential common shares (in shares)		2,037	2,066	2,079	2,023
Denominator for diluted earnings per share - adjusted weighted average shares (in shares)		419,121	406,673	415,775	400,096
Basic earnings per share (in dollars per share)		$ 0.43	$ 0.34	$ 1.18	$ 1.05
Diluted earnings per share (in dollars per share)	[1]	$ 0.42	$ 0.34	$ 1.17	$ 1.05

[1] Includes adjustment to the numerator for income (loss) attributable to OP unitholders.