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Accounting and Reporting Changes - Additional Information (Detail) - USD ($) $ in Thousands | Apr. 01, 2019 | Sep. 30, 2019 | Jun. 24, 2019 | Mar. 31, 2019
--- | --- | --- | --- | ---
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |
Right-of-use assets |  | $ 312 |  |
Lease liabilities |  | 305 |  |
Retained earnings |  | $ 92,979 |  | $ 93,847
Topic 842 [Member] |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |
Right-of-use assets | $ 676 |  |  |
Lease liabilities | 732 |  |  |
Retained earnings | 80 |  |  |
Decrease in other current assets | 47 |  |  |
Decrease in deferred income tax liability | $ 20 |  |  |
Topic 842 [Member] | Held for Sale [Member] |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |
Right-of-use assets |  |  |  | 500
Lease liabilities |  |  |  | $ 500
Topic 842 [Member] | Subsequently Sold [Member] |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |
Right-of-use assets |  |  | $ 500 |
Lease liabilities |  |  | $ 500 |
Topic 842 [Member] | Maximum [Member] |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |
Lease term | 12 months |  |  |

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