Income Taxes - Significant Portions of Deferred Tax Assets and Liabilities Due to Temporary Differences (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Classified as follows:
Deferred charges and other assets (Note 15)	$ 6,774	$ 5,797
Other long-term liabilities	(9,987)	(3,856)
Net deferred tax liabilities	$ (3,213)
Net deferred tax assets		$ 1,941

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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