The provision for income taxes from continuing operations differs from the federal statutory rate of 21% for the years ended December 31, 2019 and 2018 and 35% for the year ended December 31, 2017 due to the following (in thousands):



	2019					2018					2017
Statutory rate	17,800			21.0	%	16,788			21.0	%	27,268			35.0	%
State taxes, less federal effect	3,219			3.8	%	3,242			4.1	%	2,442			3.1	%
Federal tax credits	(1,967		)	(2.3	)%	(3,680		)	(4.6	)%	(373		)	(0.5	)%
Excess tax benefit on stock based compensation	(961		)	(1.1	)%	(2,288		)	(2.9	)%	(1,415		)	(1.8	)%
Uncertain tax positions	(260		)	(0.3	)%	(3,051		)	(3.8	)%	(148		)	(0.2	)%
Executive compensation	1,132			1.3	%	1,369			1.7	%	160			0.2	%
Change in valuation allowance	88			0.1	%	844			1.1	%	660			0.8	%
Net operating loss (NOL) write down	—			—	%	1,640			2.1	%	—			—	%
Change in Indemnification Asset	—			—	%	643			0.8	%	—			—	%
Tax effect of Tax Reform Act	—			—	%	—			—	%	(12,535		)	(16.1	)%
Domestic manufacturer's deduction	—			—	%	—			—	%	(1,578		)	(2.0	)%
Other	621			0.7	%	629			0.7	%	462			0.7	%
	$	19,672		23.2	%	$	16,136		20.2	%	$	14,943		19.2	%

Income taxes paid and net of tax refunds [Table Text Block].

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Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years.

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Tabular disclosure for tax positions taken in the tax returns filed or to be filed for which it is more likely than not that the tax position will not be sustained upon examination by taxing authorities and other income tax contingencies. Includes, but is not limited to, interest and penalties, reconciliation of unrecognized tax benefits, unrecognized tax benefits that would affect the effective tax rate, tax years that remain subject to examination by tax jurisdictions, and information about positions for which it is reasonably possible that amounts unrecognized will significantly change within 12 months.

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