CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock Member	Additional Paid In Capital Member	Retained Earnings Member	Accumulated Other Comprehensive Loss Member	Treasury Stock Member
Beginning Balance at Dec. 31, 2013		$ 49,190	$ 150,618	$ 1,380,981	$ 25,259	$ (53,343)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings				113,338
Other comprehensive loss, net of tax	$ (153,670)				(153,670)
Dividends paid/declared				(25,013)
Restricted stock			(722)			3,155
Stock options exercised, net of tax		0	311			45,049
Other			(430)			430
Share-based compensation			8,266			234
Repurchases of common stock						(65,220)
Ending Balance at Dec. 31, 2014	1,478,433	49,190	158,043	1,469,306	(128,411)	(69,695)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	75,612			75,612
Other comprehensive loss, net of tax	(56,604)				(56,604)
Dividends paid/declared				(18,240)
Restricted stock			(5,793)			8,206
Stock options exercised, net of tax		0	(2,585)			19,031
Other			(623)			623
Share-based compensation			6,931			294
Repurchases of common stock						(185,224)
Ending Balance at Sep. 30, 2015	$ 1,320,061	$ 49,190	$ 155,973	$ 1,526,678	$ (185,015)	$ (226,765)