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Income Taxes - Additional Information (Detail) - USD ($) |  | 6 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Apr. 02, 2018 | Sep. 30, 2018 | Dec. 31, 2017 | Mar. 31, 2018
Income Taxes [Line Items] |  |  |  |
Liability unrecognized tax benefits |  | $ 0 |  | $ 0
Percentage of corporate income tax rate |  | 21.00% | 35.00% |
Income tax benefit from remeasurement of deferred tax assets and liabilities |  |  |  | 971,000
One-time transition tax on accumulated foreign earnings |  |  |  | $ 185,000
Incremental tax on GILTI estimated amount |  | $ 30,000 |  |
Foreign derived intangible income (FDII) effective tax rate |  |  | 13.125% |
Estimated incremental U.S. tax savings on foreign derived intangible income | $ 200,000 |  |  |
Earliest Tax Year [Member] | Federal Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year |  | 2015 |  |
Earliest Tax Year [Member] | State Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year |  | 2013 |  |
Earliest Tax Year [Member] | International Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year |  | 2015 |  |
Latest Tax Year [Member] | Federal Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year |  | 2017 |  |
Latest Tax Year [Member] | State Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year |  | 2017 |  |
Latest Tax Year [Member] | International Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Open tax year |  | 2017 |  |

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- Definition The amount of estimated incremental U.S. tax to be incurred related to the global intangible low-taxed income provisions of the Tax Cuts and Jobs Act. + References No definition available. + Details
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- Definition One-time transition tax on accumulated post-1986 earnings and profits of foreign subsidiary previously deferred from U.S. income taxes. + References No definition available. + Details
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