Income Taxes - Tax Effect of Significant Items Comprising the Net Deferred Tax Asset (Liability) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax asset:
Benefits from net operating loss carryforwards	$ 7,112	$ 5,551
Long-term incentive compensation plans	22,363	20,907
Investment basis differences	5,256	4,376
Depreciation and amortization	2,065	1,554
Lease liability	5,994	6,409
Other, primarily accrued expenses deductible when paid	4,737	3,106
Deferred tax assets, gross	47,527	41,903
Less: valuation allowance	(3,025)	(2,026)
Deferred tax asset	44,502	39,877
Deferred tax liability:
Intangible assets	7,933	8,013
Investment in foreign subsidiaries	3,048	2,191
Right-of-use asset	4,975	5,191
Other	1,760	1,672
Deferred tax liability	17,716	17,067
Net deferred tax asset	$ 26,786	$ 22,810

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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