Equity - Summary of Unvested Shares of Restricted Common Stock (Detail) (Restricted Incentive [Member], USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2014
Restricted Incentive [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Restricted Shares of Common Stock	598,815
Granted, Restricted Shares of Common Stock	529,100
Vested, Restricted Shares of Common Stock	(147,009)
Forfeited, Restricted Shares of Common Stock	(7,386)
Ending Balance, Restricted Shares of Common Stock	973,520
Beginning Balance, Fair Value of Restricted Shares of Common Stock	$ 7,484
Granted, Fair Value of Restricted Shares of Common Stock	7,504
Vested, Fair Value of Restricted Shares of Common Stock	(1,838)
Forfeited, Fair Value of Restricted Shares of Common Stock	(98)
Ending Balance, Fair Value of Restricted Shares of Common Stock	$ 13,052