Net Income per Share (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Net Income per Share [Abstract]
Net income (loss)	$ 7,591	[1]	$ 3,526	[1]
Less: earnings allocated to RSUs	(263)		(127)
Net income (loss) available to common shareholders	$ 7,328		$ 3,399

[1] There is no material difference between net income and comprehensive income.