Debt - Schedule of Reconciliation of Interest Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Debt Instrument [Line Items]
Amortization of debt discount/premium, net	$ 1,125	$ 1,042	$ 2,227	$ 2,074
Amortization of financing costs	1,994	1,752	3,852	3,498
Other interest	116	173	235	315
Interest expense	24,839	21,275	47,394	42,336
Corporate level [Member]
Debt Instrument [Line Items]
Project-level interest and commitment fees incurred	8,497	4,952	15,612	10,005
Project level [Member]
Debt Instrument [Line Items]
Project-level interest and commitment fees incurred	$ 13,107	$ 13,356	$ 25,468	$ 26,444