Contingently Issuable Common Stock (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	0 Months Ended	3 Months Ended
	Dec. 10, 2010	Mar. 31, 2014	Mar. 31, 2013
Business Combinations [Abstract]
Purchase price common shares	3.2
Common shares value	$ 19,400,000
closing stock price		$ 12.87
Number of Shares, Contingently Issuable	10.2	3.7
Estimated fair value of Contingent payment	28,200,000
Contingent consideration, at fair value hypothetical value		47,600,000
Business acquisition, increase (decrease) common stock		$ (4.57)
Business acquisition, percentage increase (decrease)		(26.20%)
Fair Value of Contingently Issuable Common Stock [Roll Forward]
December 31, 2013		60,900,000
Fair value adjustment of Contingent Payment for three months ended March 31, 2014		(11,800,000)	5,200,000
March 31, 2014		$ 49,100,000