Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Total stockholders' equity	Noncontrolling Interests
Balance, Value at Dec. 31, 2017	$ 3,483,025	$ 1	$ 2,236,351	$ 1,311,112	$ (67,509)	$ 3,479,955	$ 3,070
Balance, Shares at Dec. 31, 2017		110,925
Cumulative-effect adjustment | Accounting Standards Update 2016-02				40,550	(40,550)
Net income (loss)	76,172			76,227		76,227	(55)
Dividends on common shares	(42,330)			(42,330)		(42,330)
Shares issued in connection with share-based compensation, value	(12,606)		(11,759)	(847)		(12,606)
Shares issued in connection with share-based compensation, shares		620
Share-based compensation	19,509		19,509			19,509
Net activity related to noncontrolling interests	(901)		189			189	(1,090)
Other comprehensive income (loss)	(50,428)				(50,409)	(50,409)	(19)
Balance, Value at Mar. 31, 2018	3,472,441	$ 1	2,244,290	1,384,712	(158,468)	3,470,535	1,906
Balance, Shares at Mar. 31, 2018		111,545
Balance, Value at Dec. 31, 2018	$ 3,745,388	$ 1	2,258,290	1,644,165	(160,575)	3,741,881	3,507
Balance, Shares at Dec. 31, 2018	111,496	111,496
Cumulative-effect adjustment | Accounting Standards Update 2016-02	$ 1,283			1,283		1,283
Net income (loss)	109,804			109,575		109,575	229
Dividends on common shares	(47,021)			(47,021)		(47,021)
Purchase of Company shares	(2,066)		(2,066)			(2,066)
Purchase of Company shares, shares		(47)
Shares issued in connection with share-based compensation, value	(11,480)		(10,618)	(862)		(11,480)
Shares issued in connection with share-based compensation, shares		623
Share-based compensation	19,597		19,597			19,597
Net activity related to noncontrolling interests	(1,286)		(60)			(60)	(1,226)
Other comprehensive income (loss)	66,317				66,318	66,318	(1)
Balance, Value at Mar. 31, 2019	$ 3,880,536	$ 1	$ 2,265,143	$ 1,707,140	$ (94,257)	$ 3,878,027	$ 2,509
Balance, Shares at Mar. 31, 2019	112,072	112,072