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Selected Balance Sheet Data - Schedule of Other Assets (Detail) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Other Assets [Line Items] |  |
Other assets Current | $ 5,742 | $ 4,711
Other assets Non-Current | 3,986 | 4,176
Mortgage servicing rights, net of amortization [Member] |  |
Other Assets [Line Items] |  |
Other assets Current | 0 | 0
Other assets Non-Current | 1,993 | 1,897
Security deposits [Member] |  |
Other Assets [Line Items] |  |
Other assets Current | 0 | 0
Other assets Non-Current | 1,475 | 1,461
Employee Notes Receivable [Member] |  |
Other Assets [Line Items] |  |
Other assets Current | 113 | 185
Other assets Non-Current | 12 | 246
Customer trust accounts and other [Member] |  |
Other Assets [Line Items] |  |
Other assets Current | 5,629 | 4,526
Other assets Non-Current | $ 506 | $ 572

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