Stockholders' Equity (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	0 Months Ended	3 Months Ended	12 Months Ended
	Feb. 10, 2014	Jun. 30, 2014	Mar. 31, 2015	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014
Class of Stock [Line Items]
Common Stock, shares authorized			180,000
Common Stock, par value per share			$ 0.0001
Class A [Member]
Class of Stock [Line Items]
Common Stock, shares authorized			139,500			139,500
Common Stock, par value per share			$ 0.0001			$ 0.0001
Common Stock, shares outstanding			66,084			65,229
Conversion of Class B shares to Class A shares, shares			2	1,319	5,398
Authorized amount	$ 30,000
Number of shares repurchased and retired during the period		6
Price per share		$ 6.50
Expiration date	Dec. 31, 2014
Class B [Member]
Class of Stock [Line Items]
Common Stock, shares authorized			40,500			40,500
Common Stock, par value per share			$ 0.0001			$ 0.0001
Common Stock, shares outstanding			4,394			4,396
Conversion of Class B shares to Class A shares, shares			(2)	(1,319)	(5,398)