Line of credit amount paid in conjunction with modification.

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Loan term of extension option.

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Percentage of aggregate principal amount of secured credit facility.

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Percentage of bank lenders representing outstanding balance of secured credit facility.

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Percentage of issuance of new common equity to holders of unsecured notes.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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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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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Gross amount of debt extinguished.

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No definition available.

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Date the credit facility terminates, in CCYY-MM-DD format.

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The effective interest rate at the end of the reporting period.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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No definition available.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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SUBSEQUENT EVENTS - Narrative (Details) - USD ($) $ in Thousands		1 Months Ended
	Mar. 21, 2021	Mar. 31, 2021	Feb. 28, 2021	Jan. 31, 2021	Dec. 31, 2020
Subsequent Event [Line Items]
Secured credit facility					$ 3,616,293
Secured credit facility, impact of uncertainty		$ 107,833
Subsequent Event
Subsequent Event [Line Items]
Loan maturity date		Feb. 28, 2026
Loan agreement term		4 years
Loan term of extension option		1 year
Subsequent Event \| Ambassador Infrastructure, LLC
Subsequent Event [Line Items]
Secured credit facility, impact of uncertainty		$ 8,250
Loan maturity date		Mar. 31, 2025
Loan agreement term		4 years
Line of credit fixed interest rate		3.00%
Amount paid in conjunction with modification		$ 1,110
Restructuring Support Agreement \| Subsequent Event
Subsequent Event [Line Items]
Percentage of bank lenders representing outstanding balance of secured credit facility		96.00%
Aggregate principal amount of secured credit facility		69.00%
Elimination of debt as result of implementation of plan	$ 1,681,900	$ 1,681,900
Principal amount of unsecured notes	1,375,000	1,375,000
New senior secured notes	555,000	555,000
Cash	95,000	95,000
Convertible secured notes	$ 100,000	$ 100,000
Percentage of issuance of new common equity to holders of unsecured notes	89.00%	89.00%
Restructuring Support Agreement \| Subsequent Event \| Subscription Option
Subsequent Event [Line Items]
Cash	$ 100,000	$ 100,000
Convertible secured notes	$ 50,000	$ 50,000
Percentage of issuance of new common equity to holders of unsecured notes	11.00%	11.00%
Restructuring Support Agreement \| Subsequent Event \| Secured Credit Facility
Subsequent Event [Line Items]
Secured credit facility	$ 133,000	$ 133,000
Restructuring Support Agreement \| Subsequent Event \| Secured Credit Facility \| Subscription Option
Subsequent Event [Line Items]
Secured credit facility	983,700	983,700
Restructuring Support Agreement \| Subsequent Event \| Secured Term Loan \| Subscription Option
Subsequent Event [Line Items]
Secured credit facility	$ 883,700	883,700
U.S Treasury Securities \| Subsequent Event
Subsequent Event [Line Items]
U.S. Treasury securities, purchased		$ 82,393	$ 31,999	$ 21,999
Debt instrument, maturity date		Jun. 30, 2021	Mar. 31, 2021	Feb. 28, 2021