Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Noncontrolling Interest
Beginning Balance at Dec. 31, 2012	$ 1,047,304	$ 860	$ 832,230	$ 264,667	$ 2,670	$ (53,615)	$ 492
Beginning Balance, Shares at Dec. 31, 2012		71,417				14,590
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Proceeds from stock options exercised	5,425	$ 3	5,422
Proceeds from stock options exercised, Shares		318
Tax benefit related to equity compensation	2,197		2,197
Stock based compensation expense	7,889		7,889
Restricted stock granted	0	$ 3	(3)
Restricted stock granted, Shares		345
Restricted stock cancelled	0
Restricted stock cancelled, Shares		(8)
Amortization of restricted stock	0		0
Dividends - Cash	(147,156)			(147,156)
Re-issuance of treasury shares (ESPP), Shares		(10)				10
Re-issuance of treasury shares (ESPP)	319		283	0		$ 36
Net income (loss)	115,197			115,135			62
Other comprehensive income (loss), net of tax	(7,199)				(7,099)		(100)
Ending Balance at Dec. 31, 2013	1,023,976	$ 866	848,018	232,646	(4,429)	$ (53,579)	454
Ending Balance, Shares at Dec. 31, 2013		72,082				14,580
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Proceeds from stock options exercised	7,281	$ 4	7,277
Proceeds from stock options exercised, Shares		386
Tax benefit related to equity compensation	2,035		2,035
Stock based compensation expense	8,909		8,909
Shares withheld for net settlements of share-based awards, shares		(54)				43
Shares withheld for net settlements of share-based awards	(1,844)		(428)			$ (1,416)
Restricted stock granted	0	$ 3	(3)
Restricted stock granted, Shares		306
Retirement of common stock	0	$ (146)	(54,826)	0		$ 54,972
Retirement of common stock, Shares		0				(14,618)
Restricted stock cancelled	0
Restricted stock cancelled, Shares		(23)
Amortization of restricted stock	0		0
Dividends - Cash	(170,234)			(170,234)
Dividends - Stock	54,725	$ (15)	54,710	0
Dividends - Stock, Shares		1,483
Purchase of treasury shares	0	$ 0	0
Purchase of treasury shares, Shares		0
Re-issuance of treasury shares (ESPP), Shares		(11)				(5)
Re-issuance of treasury shares (ESPP)	387		364	0		$ 23
Net income (loss)	143,840			143,930			(90)
Other comprehensive income (loss), net of tax	(23,082)				(23,032)		(50)
Ending Balance at Dec. 31, 2014	1,045,993	$ 742	866,056	206,342	(27,461)	$ 0	314
Ending Balance, Shares at Dec. 31, 2014		74,191				0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Proceeds from stock options exercised	$ 2,775	$ 1	2,774
Proceeds from stock options exercised, Shares	123	123
Tax benefit related to equity compensation	$ 1,409		1,409
Stock based compensation expense	11,709		11,709
Shares withheld for net settlements of share-based awards, shares		(72)
Shares withheld for net settlements of share-based awards	(2,786)		(2,786)
Restricted stock granted	0	$ 4	(4)
Restricted stock granted, Shares		423
Restricted stock cancelled	0	$ 0
Restricted stock cancelled, Shares		(35)
Dividends - Cash	(186,984)			(186,984)
Shares issued for ESPP		13
Issuance of common stock (ESPP)	441		441
Net income (loss)	139,315			139,438			(123)
Other comprehensive income (loss), net of tax	(5,035)				(4,943)		(92)
Ending Balance at Dec. 31, 2015	$ 1,006,837	$ 747	$ 879,599	$ 158,796	$ (32,404)	$ 0	$ 99
Ending Balance, Shares at Dec. 31, 2015		74,643				0