Basic And Diluted Net Income Per Common Share (Computation Of Basic And Diluted Net Income Per Common Share) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended														12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011		Jun. 30, 2011		Mar. 31, 2011	Dec. 31, 2010		Sep. 30, 2010		Jun. 30, 2010		Mar. 31, 2010		Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Basic And Diluted Net Income Per Common Share [Abstract]
Net income available to common shareholders	$ 4,941	$ 14,515	[1]	$ 11,291	[2]	$ 8,477	$ 12,506	[3]	$ 9,952	[4]	$ 2,916	[5]	$ 9,476	[6]	$ 39,224	$ 34,850	$ 39,159
Basic	56,381	56,275	[1]	56,188	[2]	56,124	56,020,000	[3]	55,904,000	[4]	55,830,000	[5]	55,708,000	[6]	56,243,015	55,866,552	54,757,279
Effect of Dilutive Securities															750,933	875,725	1,771,994
Diluted	57,032	56,983	[1]	57,054	[2]	56,893	56,816,000	[3]	56,686,000	[4]	56,748,000	[5]	56,725,000	[6]	56,993,948	56,742,277	56,529,273
Basic net income per common share	$ 0.09	$ 0.26	[1]	$ 0.20	[2]	$ 0.15	$ 0.22	[3]	$ 0.18	[4]	$ 0.05	[5]	$ 0.16	[6]	$ 0.70	$ 0.62	$ 0.72
Diluted net income per common share	$ 0.09	$ 0.25	[1]	$ 0.20	[2]	$ 0.15	$ 0.22	[3]	$ 0.18	[4]	$ 0.05	[5]	$ 0.16	[6]	$ 0.69	$ 0.61	$ 0.69

[1] Includes $2.8 million of net earnings related to a reversal of net uncertain tax positions (Refer to Note 12 of the Company's consolidated financial statements contained in Item 8 of this Annual Report for further information).

[2] Includes a $1.3 million, pre-tax, reduction in an environmental liability. Refer to Note 16 of the Company's consolidated financial statements contained in Item 8 of this Annual Report for further information.

[3] Includes a $0.9 million loss on debt extinguishment and a $0.3 million charge related to a litigation contingency. Refer to Note 16 of the Company's consolidated financial statements contained in Item 8 of this Annual Report for further information.

[4] Includes $3.5 million of net earnings related to a reduction in valuation allowance associated with foreign tax credits and a net $0.5 million of charges related to litigation and other contingencies. Refer to Notes 12 and 16 of the Company's consolidated financial statements contained in Item 8 of this Annual Report for further information.

[5] Includes an $11.5 million charge related to a litigation contingency. Refer to Note 16 of the Company's consolidated financial statements contained in Item 8 of this Annual Report for further information.

[6] Includes a $2.7 million gain on acquisitions. The results of the last three quarters of 2010 include the impacts of the first quarter 2010 acquisitions. Refer to Note 2 of the Company's consolidated financial statements contained in Item 8 of this Annual Report for further information.