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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 |

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