Income Taxes - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		12 Months Ended
	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Line Items]
Deferred tax liabilities		$ 11,466,000	$ 86,099,000		$ 11,466,000	$ 86,099,000
Foreign tax credit carry forwards		5,300,000			$ 5,300,000
Foreign tax credit carryforwards, expiration start year					2023
Foreign tax credit carryforwards, expiration end year					2024
Income tax provision (benefit), federal rate					35.00%	35.00%	35.00%
Estimated income tax benefit		67,000,000
Net income tax provision					$ 34,205,000
Income tax benefit valuation allowance					$ 101,000,000
Effective income tax rate from continuing operations					14.70%	23.30%
Cash distribution from foreign subsidiaries to parent	$ 72,500
Indefinitely reinvested foreign earnings		0			$ 0
Change in position of prior year foreign tax credits					8,410,000
Unrecognized tax benefit		354,000	7,470,000		354,000	$ 7,470,000	$ 7,470,000	$ 1,180,000
Unrecognized tax benefit that would affect the effective tax rate if recognized		500,000			500,000
Unrecognized tax benefit reduction due to settlements with taxing authorities and or statute of limitations expirations					400,000
Unrecognized tax benefit, interest accrued		900,000	200,000		900,000	200,000	1,200,000
Unrecognized tax benefit, penalties accrued		0	$ 0		0	$ 0	$ 0
Internal Revenue Service (IRS) | Minimum
Income Taxes [Line Items]
Income tax, years under examination			2014
New York City Audit
Income Taxes [Line Items]
Income tax examination resulted tax charge					$ 2,000,000
Earliest Tax Year | New York City Audit
Income Taxes [Line Items]
Income tax, years under examination					2007
Latest Tax Year | New York City Audit
Income Taxes [Line Items]
Income tax, years under examination					2014
Scenario, Forecast
Income Taxes [Line Items]
Income tax provision (benefit), federal rate				21.00%
Federal
Income Taxes [Line Items]
Operating loss carry forwards		20,400,000			$ 20,400,000
Operating loss carry forwards, expiration year					2035
State and Local Jurisdiction
Income Taxes [Line Items]
Operating loss carry forwards		$ 22,800,000			$ 22,800,000
Operating loss carry forwards, expiration start year					2034
Operating loss carry forwards, expiration end year					2035
State Jurisdiction | Minimum
Income Taxes [Line Items]
Income tax, years under examination			2011