Income Taxes

Income tax expense was as follows:



	Three Months Ended September 30,						Nine Months Ended September 30,
	2017			2016			2017			2016
Current income tax expense	$	15,224		$	12,848		$	44,636		$	40,251
Deferred income tax expense (benefit)	(5,332		)	(1,996		)	(9,505		)	(11,629		)
Income tax expense, as reported	$	9,892		$	10,852		$	35,131		$	28,622

Effective tax rate	9.6		%	11.9		%	11.8		%	11.5		%

Net deferred tax assets totaled $28.9 million at September 30, 2017 and $63.7 million at December 31, 2016. No valuation allowance for deferred tax assets was recorded at September 30, 2017 as management believes it is more likely than not that all of the deferred tax assets will be realized because they were supported by recoverable taxes paid in prior years.

The effective income tax rates differed from the U.S. statutory rate of 35% during the comparable periods primarily due to the effect of tax-exempt income from loans, securities and life insurance policies and the income tax effects associated with stock-based compensation. The effective income tax rates for the three and nine months ended September 30, 2017 were also impacted by the correction of an over-accrual of taxes that resulted from incorrectly classifying certain tax-exempt loans as taxable for federal income tax purposes since 2013. As a result, we recognized tax benefits totaling $3.7 million, which included $2.9 million related to the 2013 through 2016 tax years and $756 thousand related to the first and second quarters of 2017. There were no unrecognized tax benefits during any of the reported periods. Interest and/or penalties related to income taxes are reported as a component of income tax expense. Such amounts were not significant during the reported periods.

We file income tax returns in the U.S. federal jurisdiction. We are no longer subject to U.S. federal income tax examinations by tax authorities for years before 2013.