Stockholders' Equity (Details 3) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	9 Months Ended	105 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Mar. 29, 2007
Share Repurchase Program
Number of shares of outstanding common stock authorized to be acquired under a stock repurchase program	7.6	7.6	1.0
Number of shares of common stock repurchased	0.2	6.8
Average price (in dollars per share)	$ 25.17	$ 11.70
Repurchased carrying basis	$ 4.9	$ 4.9