Organization and Significant Accounting Policies - Supplemental Cash Flow Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Accounting Policies [Abstract]
Interest paid, net of interest capitalized	$ 16,072	$ 22,265
Interest paid, including interest capitalized	18,291	23,866
Income tax payments, net	1,124	1,039
Non-cash investing and financing activities:
Dividends and distributions payable	24,074	21,805
Construction and property capital expenditure cost accruals, increase (decrease)	4,497	(2,350)
Adjustments to equity related to redeemable common units and other, net increase (decrease)	517	(1,064)
Common stock 401k matching contribution	$ 0	$ 658