Consolidated Statement of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 369,771	$ 447,558	$ 546,847
Foreign currency translation adjustments	16,470	(28,478)	25,462
Total comprehensive income	386,241	419,080	572,309
Total comprehensive income attributable to noncontrolling interests	(176)	(191)	(195)
Total comprehensive income attributable to common stockholders	$ 386,065	$ 418,889	$ 572,114