Equity - Summary of the Components of Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance			$ 962,140	$ 693,744
Other comprehensive loss before reclassifications			(672)
Amounts reclassified from accumulated other comprehensive loss to interest expense			1,090	1,671
Net current period other comprehensive income (loss)	$ 662	$ 1,613	418	(2,794)
Less other comprehensive loss attributable to noncontrolling interests			7	(63)
Ending Balance	1,261,203	945,558	1,261,203	945,558
Accumulated Other Comprehensive Income
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance			3,445	(3,033)
Net current period other comprehensive income (loss)			425	(2,731)
Other comprehensive income (loss) attributable to common stockholders			425	(2,731)
Ending Balance	$ 3,870	$ (5,764)	$ 3,870	$ (5,764)