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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Income Tax [Line Items] |  |  |  |  |  |  |  |  |
Accumulated undistributed earnings of certain foreign subsidiaries | $ 28.9 |  |  |  | $ 28.0 | $ 28.9 | $ 28.0 |  |
Deferred tax asset, federal net operating loss carryforwards | 3.0 |  |  |  | 4.0 | 3.0 | 4.0 |  |
Deferred tax asset, state net operating loss carryforwards | 6.8 |  |  |  | 6.8 | 6.8 | 6.8 |  |
Deferred tax asset, foreign net operating loss carryforwards | 9.2 |  |  |  | 5.2 | 9.2 | 5.2 |  |
Deferred tax asset, U.S. research tax credit carryforwards | 1.1 |  |  |  | 1.5 | 1.1 | 1.5 |  |
Deferred tax asset, U.S. foreign tax credits carryforwards | 1.5 |  |  |  | 8.3 | 1.5 | 8.3 |  |
Deferred tax asset, U.S. alternative minimum tax credits carryforwards | 1.0 |  |  |  | 3.3 | 1.0 | 3.3 |  |
Deferred Tax Asset, Valuation Allowance | 7.7 |  |  |  | 5.9 | 7.7 | 5.9 |  |
Total deferred tax assets | 86.2 |  |  |  | 96.6 | 86.2 | 96.6 |  |
Income taxes paid |  |  |  |  |  | 13.3 | 9.6 | $ 7.2 |
Unrecognized tax benefits | 1.8 |  |  |  | 2.2 | 1.8 | 2.2 | 2.0 | $ 3.9
Unrecognized tax benefits that, interests | 0.6 |  |  |  | 0.8 | 0.6 | 0.8 |  |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued | 2.1 |  |  |  | 2.5 | 2.1 | 2.5 |  |
Decrease in valuation allowance | 2.2 |  |  |  |  |  |  | 3.5 |
Income tax expense (benefit) |  |  |  |  | (1.4) | $ 17.4 | $ 34.1 | $ 23.7 |
Effective Income Tax Rate Reconciliation, Percent |  |  |  |  |  | 30.60% | 34.10% | 28.40% |
Benefit associated with tax planning strategy |  |  |  |  | (4.2) |  | $ 4.2 |  |
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount | 0.2 | $ 0.4 | $ 0.4 | $ 0.5 | 2.4 |  | 2.4 |  |
Unrecognized tax benefits, period increase (decrease) |  |  |  |  |  |  |  | $ (1.0) |
Change in enacted tax rate |  |  |  |  | $ 0.4 |  | 0.4 | $ 0.4 |
Research Tax Credit Carryforward |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |
Deferred tax asset, tax credit carryforwards expiration year |  |  |  |  |  | 2019 |  |  |
Canada |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |
Decrease in valuation allowance | 3.5 |  |  |  |  |  |  |  |
Internal Revenue Service (IRS) |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |
Deferred tax asset, net operating loss carryforwards expiration year |  |  |  |  |  | 2027 |  |  |
State and Local Jurisdiction |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |
Deferred tax asset, net operating loss carryforwards expiration year |  |  |  |  |  | 2017 |  |  |
Foreign Tax Authority |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |
Deferred tax asset, net operating loss carryforwards expiration year |  |  |  |  |  | 2025 |  |  |
Deferred tax asset, tax credit carryforwards expiration year |  |  |  |  |  | 2023 |  |  |
Decrease in valuation allowance | (1.9) |  |  |  |  |  |  |  |
UNITED KINGDOM |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |
Deferred Tax Asset, Valuation Allowance | 5.8 |  |  |  |  | $ 5.8 |  |  |
Decrease in valuation allowance | $ (1.3) |  |  |  |  |  |  |  |
Current Deferred Tax Assets [Member] |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |
Unrecognized tax benefits, period increase (decrease) |  |  |  |  |  | $ (0.3) | $ (0.5) |  |

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