SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
ValuationAndQualifyingAccountsDisclosureLineItems
Valuation Allowances and Reserves, Balance, Beginning Balance	$ 12,322	$ 17,776	$ 17,895
ValuationAllowancesAndReservesChargedToCostAndExpense	108	1,471	1,951
ValuationAllowancesAndReservesChargedToOtherAccounts	17	125	(181)
ValuationAllowancesAndReservesDeductions	801	7,050	1,889
Valuation Allowances and Reserves, Balance, Ending Balance	11,646	12,322	17,776
Reduction of US corporate income tax rate		4,300
ValuationAllowanceOfDeferredTaxAssetsMember
ValuationAndQualifyingAccountsDisclosureLineItems
Valuation Allowances and Reserves, Balance, Beginning Balance	12,322	17,776	17,895
ValuationAllowancesAndReservesChargedToCostAndExpense	108	1,471	1,951
ValuationAllowancesAndReservesChargedToOtherAccounts	17	125	(181)
ValuationAllowancesAndReservesDeductions	801	7,050	1,889
Valuation Allowances and Reserves, Balance, Ending Balance	$ 11,646	$ 12,322	$ 17,776