CONSOLIDATED STATEMENTS OF EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock Par Value [Member]	Capital in Excess of Par Value [Member]	Retained Earnings/(Accumulated Deficit) [Member]	Accumulated Other Comprehensive Income (Loss) ("AOCI") [Member]	Treasury Stock [Member]	Stockholder's Equity [Member]	Noncontrolling Interest ("NCI") [Member]
Beginning Balance at Dec. 31, 2015					$ (93,955)
Net income	$ 35,753
Other comprehensive income (loss), net of tax	26,591				26,623
Ending Balance at Sep. 30, 2016					(67,332)
Beginning Balance at Jun. 30, 2016					(65,875)
Net income	16,392
Other comprehensive income (loss), net of tax	(1,468)				(1,457)
Ending Balance at Sep. 30, 2016					(67,332)
Beginning Balance at Dec. 31, 2016	1,595,468	$ 249,690	$ 1,695,119	$ (226,767)	(66,895)	$ (94,957)	$ 1,556,190	$ 39,278
Net income	153,580			153,030			153,030	550
Other comprehensive income (loss), net of tax	13,273				13,291		13,291	(18)
Common stock issued		43,635	(43,635)
Stock-based compensation charges	13,046		13,046				13,046
Purchase of treasury shares	(7,126)					(7,126)	(7,126)
Retirement of common stock		(822)	(5,016)			5,838
Acquisition of NCI	(6,775)		2,121		2,284		2,121	(8,896)
Other	(1,541)		(1,521)				(1,521)	(20)
Ending Balance at Sep. 30, 2017	1,759,925	292,503	1,660,114	(73,737)	(53,604)	(96,245)	1,729,031	30,894
Beginning Balance at Jun. 30, 2017					(56,191)
Net income	92,926
Other comprehensive income (loss), net of tax	2,587				2,587
Ending Balance at Sep. 30, 2017	$ 1,759,925	$ 292,503	$ 1,660,114	$ (73,737)	$ (53,604)	$ (96,245)	$ 1,729,031	$ 30,894