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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2020
Income Tax Contingency [Line Items]
Income tax expense (benefit)	$ (3.1)	$ 1.0	$ (4.8)	$ 2.6
Approximate rate on pre-tax income	27.20%	27.80%
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			2013
State Tax Authority [Member] | Earliest Tax Year [Member] | State of New York [Member]
Income Tax Contingency [Line Items]
Tax year being audited in income tax examination			2014
State Tax Authority [Member] | Earliest Tax Year [Member] | State of Massachusetts [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			2017
State Tax Authority [Member] | Latest Tax Year [Member] | State of New York [Member]
Income Tax Contingency [Line Items]
Tax year being audited in income tax examination			2016
State Tax Authority [Member] | Latest Tax Year [Member] | State of Massachusetts [Member]
Income Tax Contingency [Line Items]
Tax year being audited in income tax examination			2016
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] | Earliest Tax Year [Member] | Switzerland Federal Tax Administration [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
Foreign Tax Authority [Member] | Latest Tax Year [Member] | Switzerland Federal Tax Administration [Member]
Income Tax Contingency [Line Items]
Tax year being audited in income tax examination			2016
Scenario Forecast [Member]
Income Tax Contingency [Line Items]
U.S. federal statutory rate					21.00%

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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