Share Repurchase Program (Details) - Common Stock [Member] - USD ($)	1 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Jan. 31, 2015	Jun. 30, 2015	Jun. 30, 2015	Dec. 31, 2014	Oct. 31, 2014	Oct. 21, 2014
Equity, Class of Treasury Stock [Line Items]
Repurchased amount		$ 109,400,000	$ 122,500,000
Shares repurchased		3,948,486
Additional shares repurchased			4,452,255
Common Stock Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Authorized amount						$ 250,000,000
Repurchased amount			$ 197,500,000
Shares repurchased			7,400,000.0
Accelerated Share Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Authorized amount					$ 75,000,000.0
Shares repurchased	391,612			2,510,460