Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019		Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting change	$ (751,437)	$ (646,946)	$ (638,401)	$ (655,447)		$ (636,585)	$ (606,442)	$ (477,686)	$ (455,890)
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 | Retained Earnings | Accounting Standard Update 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting change				3,000
Cumulative Effect, Period of Adoption, Adjustment | Mezzanine Loan | Retained Earnings | Accounting Standard Update 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting change				2,800
Cumulative Effect, Period of Adoption, Adjustment | Construction Receivables | Retained Earnings | Accounting Standard Update 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting change				$ 200

[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.