Equity - Schedule of Details Movement in Our Outstanding Class A Common Stock and Restricted Class A Common Stock (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Equity [Abstract]
Beginning balance	3,016,407	2,277,344	2,243,490
Issuance of class A common stock	25,875,000	669,047
Issuance of restricted class A common stock, net	700,000	36,493	26,161
Issuance of deferred stock units	11,477	33,523	7,693
Ending balance	29,602,884	3,016,407	2,277,344