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Selected Balance Sheet Data - Schedule of Other Assets (Detail) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Other Assets [Line Items] |  |
Other assets Current | $ 6,067 | $ 6,368
Other assets Non-Current | 70,994 | 31,778
Mortgage servicing rights [Member] |  |
Other Assets [Line Items] |  |
Other assets Current | 0 | 0
Other assets Non-Current | 2,002 | 2,209
Due from independent contractors, net [Member] |  |
Other Assets [Line Items] |  |
Other assets Current | 2,882 | 3,831
Other assets Non-Current | 66,647 | 27,157
Security deposits [Member] |  |
Other Assets [Line Items] |  |
Other assets Current | 0 | 0
Other assets Non-Current | 1,345 | 1,196
Employee Notes Receivable [Member] |  |
Other Assets [Line Items] |  |
Other assets Current | 65 | 156
Other assets Non-Current | 323 | 370
Customer trust accounts and other [Member] |  |
Other Assets [Line Items] |  |
Other assets Current | 3,120 | 2,381
Other assets Non-Current | $ 677 | $ 846

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