Supplemental Disclosure to Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplemental Disclosure to Statements of Cash Flows [Abstract]
Write-off of fully depreciated/amortized property and deferred costs	$ 41,406	$ 42,339	$ 38,131
Write-off of depreciated property and deferred costs due to sale/demolition	461,480	252,017	173,083
Write-off of costs related to early debt extinguishment	219	0	0
Increase in investments in and advances to unconsolidated joint ventures due to disposition/development activity	0	0	(11,948)
Changes in accrued development capital expenditures	(11,368)	11,964	6,264
Unrealized gain (loss) on cash flow hedge	410	(488)	(3,419)
Capitalized equity-based compensation	1,221	876	1,045
Redemption of noncontrolling interests - common units	$ 132	$ 0	$ 0