Notes Payable, Net (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Promissory note issued	$ 617,198,000	$ 616,046,000
Unamortized debt issuance costs and discount	(7,802,000)	(8,954,000)
Outstanding letters of credit	1,300,000	2,400,000
Unsecured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Senior unsecured revolving credit facility, maximum borrowing capacity	125,000,000.0
Outstanding letters of credit	300,000
Senior unsecured revolving credit facility, available borrowing capacity	$ 124,700,000
7.875% Senior Notes due 2025 \| Senior Notes
Debt Instrument [Line Items]
Interest rate on new notes	7.875%
Promissory note issued	$ 625,000,000	$ 625,000,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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