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v3.19.1

Note Receivables - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Interest rate | 5.00% |  |
Percentage of interest rate increase at the event of default | 10.00% |  |
Promissory note maturity date | Dec. 29, 2021 |  |
Interest income recognized | $ 595 | $ 416 |
Fair Value, Inputs, Level 2 [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Fair value of notes receivable | $ 28,802 |  | $ 27,618

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