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Income Taxes - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017 | Mar. 31, 2017 | Jun. 30, 2018 | Dec. 31, 2017 | Mar. 31, 2018 | Mar. 31, 2017 | Jun. 30, 2018
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
U.S. federal statutory rate |  |  |  |  | 35.00% |  |  |
Tax Act, incomplete accounting, provisional adjustments |  | $ (32,600,000) |  |  |  |  |  |
Earnings per share increase |  | $ 0.45 |  |  |  |  |  |
Tax Act, limitation on deduction of executive compensation | $ 1,000,000 |  |  |  |  |  |  |
Tax Act, incomplete accounting, transition tax for accumulated foreign earnings, provisional income tax expense | 0 |  |  |  |  |  |  |
Income tax expense (benefit) | $ 5,200,000 |  | $ 3,800,000 |  |  | $ (17,700,000) | $ 15,200,000 |
Income tax expense benefit excluding change in enacted tax rate |  |  |  |  |  | $ 14,900,000 |  |
Approximate rate on pre-tax income | 31.50% |  | 47.50% |  |  |  | 63.10% |
Effective income tax rate continuing operations excluding change in enacted tax rate |  |  |  |  |  | 14.00% |  |
Foreign Tax Authority [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
Tax Act, incomplete accounting, provisional adjustments | $ 0 |  |  |  |  |  |  |
Foreign Tax Authority [Member] | Earliest Tax Year [Member] | Canada Revenue Agency [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
Tax year being audited in income tax examination |  |  |  |  |  | 2014 |  |
Foreign Tax Authority [Member] | Earliest Tax Year [Member] | Federal Ministry of Finance, Germany [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
Tax year being audited in income tax examination |  |  |  |  |  | 2013 |  |
Foreign Tax Authority [Member] | Latest Tax Year [Member] | Canada Revenue Agency [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
Tax year being audited in income tax examination |  |  |  |  |  | 2015 |  |
Foreign Tax Authority [Member] | Latest Tax Year [Member] | Federal Ministry of Finance, Germany [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
Tax year being audited in income tax examination |  |  |  |  |  | 2015 |  |
U.S. Tax Authority [Member] | Tax Year 2014 [Member] | IRS [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
Tax year being audited in income tax examination |  |  |  |  |  | 2014 |  |
U.S. Tax Authority [Member] | Tax Year 2015 [Member] | IRS [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
Tax year being audited in income tax examination |  |  |  |  |  | 2015 |  |
State Tax Authority [Member] | Earliest Tax Year [Member] | State of New Jersey [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
Tax year being audited in income tax examination |  |  |  |  |  | 2007 |  |
State Tax Authority [Member] | Earliest Tax Year [Member] | State of Wisconsin [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
Tax year being audited in income tax examination |  |  |  |  |  | 2014 |  |
State Tax Authority [Member] | Latest Tax Year [Member] | State of New Jersey [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
Tax year being audited in income tax examination |  |  |  |  |  | 2013 |  |
State Tax Authority [Member] | Latest Tax Year [Member] | State of Wisconsin [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
Tax year being audited in income tax examination |  |  |  |  |  | 2016 |  |
Scenario, Plan [Member] |  |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |
U.S. federal statutory rate |  |  |  | 21.00% |  |  |  | 28.00%

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