Property And Equipment, Net (Details) (USD $)	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Property And Equipment, Net [Abstract]
Building	$ 39,273,000		$ 39,297,000
Furniture and fixtures	17,324,000		17,249,000
Machinery and equipment	9,425,000		9,163,000
Computer equipment	65,180,000		65,331,000
Computer software	52,648,000		51,541,000
Leasehold improvements	18,765,000		18,615,000
Land	16,317,000		16,317,000
Construction in progress - building	10,458,000		6,427,000
Property and equipment, gross	229,390,000		223,940,000
Less accumulated depreciation and amortization	(131,853,000)		(129,338,000)
Property and equipment, net	97,537,000		94,602,000
Depreciation and amortization expense	$ 3,700,000	$ 3,900,000