For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Face (par) amount of debt instrument at time of issuance.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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Represents the minimum number of days for which lease rent and maintenance reserve payments are past due.

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Organization and Summary of Significant Accounting Policies - Organization and Revenue Recognition (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020	May 31, 2021 USD ($) debtSeries	Mar. 31, 2020 USD ($) debtSeries
Revenue Recognition
Lease rent receivables past due	$ 6.8
Maintenance reserve receivables past due	$ 4.1
Minimum number of days for which lease rent and maintenance reserve payments are past due	30 days
Unbilled revenue associated with outstanding contracts	$ 0.9
Revenue Benchmark \| Customer Concentration Risk \| One Customer
Revenue Recognition
Concentration risk, percentage, more than	10.00%	10.00%
WEST III
Organizations [Line Items]
Subsidiary, percentage owned	100.00%
WEST IV
Organizations [Line Items]
Subsidiary, percentage owned	100.00%
WEST V \| WEST V Notes
Organizations [Line Items]
Aggregate principal amount				$ 366.2
Number of debt series issued \| debtSeries				3
WEST V \| WEST V Series A Notes
Organizations [Line Items]
Aggregate principal amount				$ 303.0
WEST V \| WEST V Series B Notes
Organizations [Line Items]
Aggregate principal amount				42.1
WEST V \| WEST V Series C Notes
Organizations [Line Items]
Aggregate principal amount				$ 21.1
WEST VI \| WEST VI Notes
Organizations [Line Items]
Aggregate principal amount			$ 336.7
Number of debt series issued \| debtSeries			3
WEST VI \| WEST VI Series A Notes
Organizations [Line Items]
Aggregate principal amount			$ 278.6
WEST VI \| WEST VI Series B Notes
Organizations [Line Items]
Aggregate principal amount			38.7
WEST VI \| WEST VI Series C Notes
Organizations [Line Items]
Aggregate principal amount			$ 19.4