Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended	12 Months Ended
	Feb. 29, 2016	Feb. 25, 2016	Feb. 25, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Subsequent Event [Line Items]
Acquisition purchase price				$ 4,100
Average price per share				$ 21.72	$ 22.09	$ 26.41
Subsequent Event [Member]
Subsequent Event [Line Items]
Shares authorized for repurchase increase	1,000,000
Shares authorized for repurchase	2,000,000
Shares repurchased		321,000	410,000
Average price per share		$ 8.43	$ 8.43
Subsequent Event [Member] | Challenger Overseas, LLC [Member]
Subsequent Event [Line Items]
Acquisition purchase price	$ 10,800