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Stock - Based Compensation - Summary of Accumulated Stock Units (Detail) - $ / shares | Jun. 30, 2020 | Dec. 31, 2019
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Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] |  |
Accumulated stock units | 148,550 | 143,362
Average price | $ 27.85 | $ 27.17

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- Definition Deferred compensation arrangement with individual accumulated stock units For deferred board fees. + References No definition available. + Details
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- Definition Deferred compensation arrangement with individual stock average price. + References No definition available. + Details
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- References No definition available. + Details
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