Equity (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Jul. 30, 2015
Treasury stock
Maximum aggregate purchase price of shares authorized for repurchase (in dollars)	$ 50,000,000	$ 50,000,000	$ 75,000,000
Purchase of treasury stock		$ 25,000,000
Number of shares repurchased	2,652,065
Average price of shares repurchased (in dollars per share)	$ 9.40