Commitments and Contingencies - Additional Information (Details) (Subsequent Event [Member], Shareholder Litigation in Relation to Acquisition [Member])
1 Months Ended
Apr. 30, 2015
complaint
shareholder
Subsequent Event [Member] | Shareholder Litigation in Relation to Acquisition [Member]
 
Loss Contingencies [Line Items]  
Number of plaintiffs 4
Number of class action complaints 4