Quarterly Financial Data (Unaudited) (Details) (USD $)	0 Months Ended	3 Months Ended													12 Months Ended
	Oct. 27, 2010	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restructuring expenses															$ 16,383,000	$ 25,832,000	$ 2,000,000
Revenue		434,366,000		375,366,000		369,380,000		351,542,000		400,319,000		358,141,000	389,329,000	348,583,000	1,530,654,000	1,496,372,000	1,405,358,000
Gross profit		214,737,000		184,386,000		182,718,000		168,532,000	[1]	190,092,000	[2]	172,890,000	190,041,000	183,987,000	750,373,000	737,010,000	735,184,000
Earnings from continuing operations															200,261,000	177,015,000	225,356,000
(Loss) income from discontinued operations															0	0	(2,958,000)
Net earnings		72,752,000	[3]	52,857,000	[3]	44,758,000	[3]	29,894,000	[3]	28,735,000	[4]	46,486,000	50,158,000	51,636,000	200,261,000	177,015,000	222,398,000
Basic earnings per share:
Continuing operations															$ 1.42	$ 1.24	$ 1.49
Discontinued operations															$ 0.00	$ 0.00	$ (0.02)
Basic earnings per share		$ 0.52		$ 0.37		$ 0.32		$ 0.21		$ 0.20		$ 0.33	$ 0.35	$ 0.36	$ 1.42	$ 1.24	$ 1.47
Diluted earnings per share:
Continuing operations															$ 1.39	$ 1.22	$ 1.47
Discontinued operations															$ 0.00	$ 0.00	$ (0.02)
Diluted earnings per share		$ 0.51		$ 0.37		$ 0.31		$ 0.21		$ 0.20		$ 0.32	$ 0.35	$ 0.35	$ 1.39	$ 1.22	$ 1.45
Litigation settlement payment	3,000,000														28,000,000
Selling General and Administrative Expense
Restructuring expenses		1,000,000		4,100,000		3,500,000		8,400,000							16,383,000	25,832,000	2,000,000
Cost of Goods Sold
Restructuring expenses															$ 591,000	$ 1,689,000	$ 0

[1] 2014 Gross profit includes restructuring expenses of $0.6 million reported in the first quarter.

[2] 2013 Gross profit includes restructuring expenses of $1.7 million reported in the fourth quarter.

[3] 2014 Net earnings includes restructuring expenses of $8.4 million reported in the first quarter, $3.5 million reported in the second quarter, $4.1 million reported in the third quarter and $1.0 million reported in the fourth quarter.

[4] 2013 Net earnings includes restructuring expenses of$27.5 million reported in the fourth quarter.