Debt (Details) - Schedule of debt consists - NEXTNAV HOLDINGS, LLC [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Debt (Details) - Schedule of debt consists [Line Items]
Senior secured loan, principal	$ 63,964	$ 23,683
Senior secured loan, paid-in-kind interest	3,554
Less unamortized discount and debt issuance costs	(8,647)	(7,851)
Total Senior secured loan	$ 58,871	$ 15,832

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

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Interest paid other than in cash for example by issuing additional debt securities. As a noncash item, it is added to net income when calculating cash provided by or used in operations using the indirect method.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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