Deferred Costs (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred leasing costs	$ 466,136	$ 453,833
Less: accumulated amortization	(260,853)	(244,723)
Deferred costs, net	$ 205,283	$ 209,110