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Significant Accounting Policies - Noncurrent Deferred Tax Assets Recorded in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Equity [Abstract] |  |  |  |
Balance at beginning of period, Pension and Postretirement Benefit Plans | $ 80.2 | $ 88.7 | $ 69.7 | $ 89.4
Tax effect of other comprehensive loss (earnings) | (0.7) | (0.8) | 9.8 | (1.5)
Balance at end of period, Pension and Postretirement Benefit Plans | $ 79.5 | $ 87.9 | $ 79.5 | $ 87.9

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- Definition Accumulated other comprehensive loss, noncurrent deferred tax assets, other comprehensive earnings, tax effect, pension and postretirement benefit plans. + References No definition available. + Details
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- Definition Accumulated other comprehensive loss, noncurrent deferred tax assets, pension and postretirement benefit plans. + References No definition available. + Details
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- References No definition available. + Details
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Period Type: | duration