Goodwill and Intangible Assets (Summary of Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 2,349	$ 2,349
Accumulated amortization	(1,581)	(1,453)
Intangible assets, net	768	896
Ancillary provider network
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	1,921	1,921
Amortization expense	128	128
Useful life	15 years
Future amortization expense, 2013	128
Future amortization expense, 2014	128
Future amortization expense, 2015	128
Future amortization expense, 2016	128
Future amortization expense, 2017	128
Future amortization expense, 2018	128
Ancillary provider network | Minimum
Finite-Lived Intangible Assets [Line Items]
Rate of attrition	2.00%
Ancillary provider network | Maximum
Finite-Lived Intangible Assets [Line Items]
Rate of attrition	8.00%
Software
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 428	$ 428