Long-Term Debt Obligations (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Future principal payments of long-term debt
2014	$ 2,000
Total	2,000	7,400
Interest expense
Interest expense on notes to former owners	97	255	795
Interest expense on borrowings and unused commitment fees	279	444	243
Letter of credit fees	731	667	622
Amortization of debt financing costs	244	229	226
Total	$ 1,351	$ 1,595	$ 1,886