Basis of Presentation, Principles of Consolidation, Stock Split and Increase of Authorized Number of Shares of Common Stock - Additional Information (Detail) (USD $)	0 Months Ended	6 Months Ended
	Dec. 19, 2013	Jun. 30, 2014	May 15, 2014	Dec. 31, 2013
Organization, Consolidation And Summary Of Significant Accounting Policies [Line Items]
Common stock split ratio	4
Stock split, additional shares distribution date		Jan. 10, 2014
Stock Split, start trading date at a new split-adjusted price		Jan. 13, 2014
Additional shares issued as a result of stock split		3
Common stock, shares authorized		200,000,000	100,000,000	100,000,000
Common stock, par value		$ 0.01		$ 0.01