Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net income	$ 165,809	$ 154,674	$ 309,791	$ 232,889
Other comprehensive income:
Change in unrealized value related to available-for-sale securities		(1,647)		(1,619)
Change in unrealized value on interest rate swap	138	17	416	205
Change in foreign currency translation adjustments		1,218		1,721
Net current-period other comprehensive income	138	(412)	416	307
Comprehensive income	165,947	154,262	310,207	233,196
Comprehensive income attributable to noncontrolling interests	(423)	(11,258)	(315)	(12,740)
Comprehensive income attributable to the Company	$ 165,524	$ 143,004	$ 309,892	$ 220,456