Contractual interest rate for funds borrowed, under the debt agreement.

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Long-Term Debt - FFG Loan Agreements (Details) - USD ($) $ in Thousands			1 Months Ended	12 Months Ended
	Apr. 01, 2019	Mar. 08, 2019	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Apr. 30, 2019
Line of Credit Facility [Line Items]
Loss on extinguishment of debt				$ (566)	$ (229)	$ 0
FFG Loan Agreements
Line of Credit Facility [Line Items]
Accelerate payment schedule		3 years
Previous payment schedule		5 years
Repayments of debt	$ 2,900		$ 566
Minimum cash balance, percentage							70.00%
Interest expense				$ 316
Loss on extinguishment of debt			$ 566
Minimum \| FFG Loan Agreements
Line of Credit Facility [Line Items]
Interest rate applicable to borrowings				0.75%
Maximum \| FFG Loan Agreements
Line of Credit Facility [Line Items]
Interest rate applicable to borrowings				2.00%