Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Restricted Cash and Cash Equivalents Items [Line Items]
Cash	$ 38,180	$ 35,748
Cash equivalents	3,442	8,998
Restricted cash	5,700	6,200
Total cash and cash equivalents	$ 47,277	50,940	$ 29,160	$ 42,679
Distribution period	7 years
Deferred compensation liability	$ 100	500
Deferred compensation plan
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	124	498
Letter of Credit
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 5,531	$ 5,696