Goodwill (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2015	Nov. 03, 2015	Dec. 31, 2014
Goodwill [Line Items]
Fair Value, Control Premium Approach	$ 502,800
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount	5.00%
Reporting Unit, Amount of Fair Value in Excess of Carrying Amount, Control Premium Approach	$ 63,300
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount, Control Premium Approach	14.00%
Fair Value Using Market Capitalization	$ 460,800
Goodwill	30,149		$ 30,149
Net Assets	439,500
Reporting Unit, Amount of Fair Value in Excess of Carrying Amount	$ 21,300
Minimum [Member]
Goodwill [Line Items]
Price per share	$ 7.88
Maximum [Member]
Goodwill [Line Items]
Price per share	$ 17.22
Subsequent Event [Member]
Goodwill [Line Items]
Fair Value, Control Premium Approach		$ 392,600
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount		20.00%
Reporting Unit, Amount of Fair Value in Excess of Carrying Amount, Control Premium Approach		$ 46,900
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount, Control Premium Approach		11.00%
Fair Value Using Market Capitalization		$ 350,600
Reporting Unit, Amount of Fair Value in Excess of Carrying Amount		$ 88,900
Share Price		$ 6.91