Discontinued Operations - Sale of Commercial Business - Schedule of Discontinued Operations and Assets Held for Sale (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Other income and expenses:
Gain on sale of Commercial Business	$ 5,000
Income tax expense	(1,100)
Total income from discontinued operations	3,935
Commercial Business [Member]
Other income and expenses:
Gain on sale of Commercial Business	5,000
Income from discontinued operations	5,000
Income tax expense	(1,065)
Total income from discontinued operations	$ 3,935

Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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+ Details

- Definition

Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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