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, 2014		$ 49,190	$ 158,043	$ 1,469,306	$ (128,411)	$ (69,695)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings				145,461
Other comprehensive loss, net of tax	$ (97,517)				(97,517)
Dividends paid/declared				(24,122)
Restricted stock			(10,303)			13,734
Stock options exercised, net of tax		0	(11,349)			45,743
Other			(647)			647
Share-based compensation			9,179			294
Repurchases of common stock						(294,130)
Ending Balance at Dec. 31, 2015	1,255,423	49,190	144,923	1,590,645	(225,928)	(303,407)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	72,782			72,782
Other comprehensive loss, net of tax	(11,409)				(11,409)
Dividends paid/declared				(11,576)
Restricted stock			(10,921)			14,450
Stock options exercised, net of tax		0	(5,161)			20,951
Other			(1,027)			735
Share-based compensation			4,560			425
Repurchases of common stock						(54,958)
Ending Balance at Jun. 30, 2016	$ 1,274,271	$ 49,187	$ 132,374	$ 1,651,851	$ (237,337)	$ (321,804)