Significant Accounting Policies - Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting change	$ (756,802)		$ (655,447)		$ (455,890)		$ (420,283)
Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting change			$ 3,009	[1]	$ 167	[2]
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standard Update 2016-13 | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting change		$ 3,000
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standard Update 2016-13 | Retained Earnings | Construction Receivables
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting change		200
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standard Update 2016-13 | Retained Earnings | Mezzanine Loan
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting change		$ 2,800

[1] The Company recorded cumulative effect adjustments related to the new Current Expected Credit Losses ("CECL") standard in the first quarter of 2020. See "Financial Statements — Note 2 — Significant Accounting Policies — Recent Accounting Pronouncements" for additional information.

[2] The Company recorded cumulative effect adjustments related to the new lease standard in the first quarter of 2019. See "Financial Statements — Note 2 — Significant Accounting Policies — Recent Accounting Pronouncements" for additional information.