Property and Equipment (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 69,506,000		$ 69,506,000		$ 67,209,000
Accumulated Depreciation	(35,392,000)		(35,392,000)		(33,102,000)
Property and equipment, net	34,114,000		34,114,000		34,107,000
Depreciation expense	2,900,000	1,900,000	5,600,000	3,500,000
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	34,716,000		34,716,000		32,528,000
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	5,104,000		5,104,000		5,126,000
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	7,139,000		7,139,000		6,992,000
Software [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	19,735,000		19,735,000		19,870,000
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 2,812,000		$ 2,812,000		$ 2,693,000