Stockholders' Equity (Details 2) - Share repurchase program December 2013 - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	9 Months Ended		22 Months Ended
	Oct. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Dec. 31, 2013
Shareholders' Equity
Total purchases authorized under share repurchase program					$ 150.0
Shares repurchased	307,600	1,263,791	1,485,141	3,341,432
Average purchase price (in dollars per share)	$ 16.60	$ 18.04	$ 20.54	$ 19.61
Amount of remaining authorization to repurchase common stock	$ 79.4