Derivative and Other Fair Value Instruments - Summary of Fair Value Measurements for Each Major Category of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Fair Value Of SERP Investments	$ 126,160	$ 151,889
Other Liabilities, Fair Value Disclosure	126,160	151,889
Liabilities, Fair Value Disclosure	127,127
Redeemable Noncontrolling Interests - Operating Partnership/Redeemable Limited Partners	353,342	463,400	$ 432,562	$ 379,106
Forward Starting Swaps [Member]
Derivatives, Fair Value [Line Items]
Forward Starting Swaps	967
Fair Value, Inputs, Level 1 [Member]
Derivatives, Fair Value [Line Items]
Fair Value Of SERP Investments	126,160	151,889
Other Liabilities, Fair Value Disclosure	126,160	151,889
Liabilities, Fair Value Disclosure	126,160
Redeemable Noncontrolling Interests - Operating Partnership/Redeemable Limited Partners	0	0
Fair Value, Inputs, Level 1 [Member] | Forward Starting Swaps [Member]
Derivatives, Fair Value [Line Items]
Forward Starting Swaps	0
Fair Value, Inputs, Level 2 [Member]
Derivatives, Fair Value [Line Items]
Fair Value Of SERP Investments	0	0
Other Liabilities, Fair Value Disclosure	0	0
Liabilities, Fair Value Disclosure	967
Redeemable Noncontrolling Interests - Operating Partnership/Redeemable Limited Partners	353,342	463,400
Fair Value, Inputs, Level 2 [Member] | Forward Starting Swaps [Member]
Derivatives, Fair Value [Line Items]
Forward Starting Swaps	967
Fair Value, Inputs, Level 3 [Member]
Derivatives, Fair Value [Line Items]
Fair Value Of SERP Investments	0	0
Other Liabilities, Fair Value Disclosure	0	0
Liabilities, Fair Value Disclosure	0
Redeemable Noncontrolling Interests - Operating Partnership/Redeemable Limited Partners	0	$ 0
Fair Value, Inputs, Level 3 [Member] | Forward Starting Swaps [Member]
Derivatives, Fair Value [Line Items]
Forward Starting Swaps	$ 0