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Organization and Summary of Significant Accounting Policies - Organization and Revenue Recognition (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Mar. 31, 2020
Revenue Recognition |  |
Lease rent receivables past due | $ 4.6 |
Maintenance reserve receivables past due | $ 1.9 |
Minimum number of days for which lease rent and maintenance reserve payments are past due | 30 days |
Unbilled revenue associated with outstanding contracts | $ 0.8 |
Revenue Benchmark | Customer Concentration Risk | One Customer |  |
Revenue Recognition |  |
Concentration risk, percentage | 11.40% |
WEST II |  |
Organizations [Line Items] |  |
Acquisition of the remaining outstanding shares | 100.00% |
WEST III |  |
Organizations [Line Items] |  |
Acquisition of the remaining outstanding shares | 100.00% |
West IV |  |
Organizations [Line Items] |  |
Acquisition of the remaining outstanding shares | 100.00% |
West V | WEST V Notes |  |
Organizations [Line Items] |  |
Aggregate principal amount |  | $ 366.2
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

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