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Summary of Significant Accounting Policies - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
RECENT ACCOUNTING PRONOUNCEMENTS
Asset held for sale less cost to sell	$ 0	$ 0	$ 7,000,000
Impairment charge	7,000,000.0	$ 7,000,000.0
Expiration period (in years)		10 years
EB-5 Loan \| Loans payable \| Level 2
RECENT ACCOUNTING PRONOUNCEMENTS
Lines of credit	$ 1,000,000.0	$ 1,000,000.0
Minimum
RECENT ACCOUNTING PRONOUNCEMENTS
Award vesting period (in years)		1 year
Maximum
RECENT ACCOUNTING PRONOUNCEMENTS
Award vesting period (in years)		3 years