Property and Equipment (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 67,209,000	$ 53,528,000
Accumulated depreciation and amortization	(33,102,000)	(36,222,000)
Property and equipment, net	34,107,000	17,306,000
Depreciation expense	8,000,000	5,700,000	5,600,000
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	32,528,000	25,101,000
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,126,000	1,811,000
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	6,992,000	3,692,000
Purchased Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	19,870,000	20,641,000
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,693,000	$ 2,283,000