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, 2015		$ 49,190	$ 144,923	$ 1,590,645	$ (225,928)	$ (303,407)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings				187,329
Other comprehensive loss, net of tax	$ (65,828)				(65,828)
Dividends paid/declared				(23,067)
Restricted stock			(12,086)			17,275
Stock options exercised			(11,271)			39,483
Other		3	(1,104)			811
Share-based compensation			9,021			457
Repurchases of common stock						(105,249)
Ending Balance at Dec. 31, 2016	1,291,191	49,187	129,483	1,754,907	(291,756)	(350,630)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	147,141			147,141
Other comprehensive loss, net of tax	74,268				74,268
Dividends paid/declared				(18,124)
Restricted stock			(9,624)			9,618
Stock options exercised			(2,995)			14,855
Other			(2,099)	(739)		750
Share-based compensation			8,808			365
Repurchases of common stock						(38,939)
Ending Balance at Sep. 30, 2017	$ 1,474,476	$ 49,187	$ 123,573	$ 1,883,185	$ (217,488)	$ (363,981)