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Stock-Based Compensation - Compensation Expense for Periods Included in Continuing Operations (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Restricted Stock Units (RSU) and Performance Share Awards (PSAs) [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Compensation expense | $ 1,292 | $ 1,161 | $ 2,377 | $ 1,595
Stock Only Stock Appreciation Rights (SOSARs) [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Compensation expense |  |  |  | $ 43

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