Income Taxes

We use the asset and liability method of accounting for income taxes. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amount of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. Such amounts are adjusted, as appropriate, to reflect changes in tax rates expected to be in effect when temporary differences reverse. The effect of a change in tax rates on deferred taxes is recognized in the period that the change is enacted. A valuation allowance is recorded to reduce the Company's deferred tax assets to the amount that is more likely than not to be realized. We had no recorded valuation allowance at March 31, 2017 and December 31, 2016.

Our effective tax rate was 28.6% and 29.3% for the three months ended March 31, 2017 and 2016, respectively. The decrease in the effective tax rate for 2017 is primarily attributable to the favorable impact of the reversal of previously recorded accruals for penalties and interest related to uncertain tax positions where the applicable statute of limitations have now lapsed.

We recognize the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that is greater than 50% likely of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. We record interest and penalties related to unrecognized tax benefits in income tax expense.

At March 31, 2017 and December 31, 2016, we had a total of $7.1 million and $8.8 million in gross unrecognized tax benefits, respectively included in long-term income taxes payable in the consolidated balance sheet. Of this amount, $4.8 million and $5.7 million represents the amount of unrecognized tax benefits that, if recognized, would impact our effective tax rate as of March 31, 2017 and December 31, 2016. Unrecognized tax benefits were a net decrease of $1.7 million and $0.8 million during the three months ended March 31, 2017 and 2016, respectively. The net decrease during the three month periods of 2017 and 2016 was mainly due to the expiration of certain statues of limitation net of additions and settlements with respective states. This had the effect of decreasing the effective state tax rate during these respective periods. The total net amount of accrued interest and penalties for such unrecognized tax benefits was $2.4 million and $3.2 million at March 31, 2017 and December 31, 2016 and is included in long-term income taxes payable in the consolidated balance sheets. Income tax expense is increased each period for the accrual of interest on outstanding positions and penalties when the uncertain tax position is initially recorded. Income tax expense is reduced in periods by the amount of accrued interest and penalties associated with reversed uncertain tax positions due to lapse of applicable statute of limitations, when applicable or when a position is settled. Net interest and penalties included in income tax expense for the three month period ended March 31, 2017 and 2016 was a net benefit of approximately $0.8 million and $0.8 million, respectively. Income tax expense decreased during the three months ended March 31, 2017 and 2016 due to reductions for rolloff exceeding accrual. These unrecognized tax benefits relate to risks associated with state income tax filing positions for our corporate subsidiaries.

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:



	2017
	(in thousands)
Balance at January 1, 2017	$	8,751
Additions based on tax positions related to current year	70
Additions for tax positions of prior years	—
Reductions for tax positions of prior years	(415		)
Reductions due to lapse of applicable statute of limitations	(1,293		)
Settlements	(17		)
Balance at March 31, 2017	$	7,096

A number of years may elapse before an uncertain tax position is audited and ultimately settled. It is difficult to predict the ultimate outcome or the timing of resolution for uncertain tax positions. It is reasonably possible that the amount of unrecognized tax benefits could significantly increase or decrease within the next twelve months. These changes could result from the expiration of the statute of limitations, examinations or other unforeseen circumstances. We do not have any outstanding litigation related to tax matters. At this time, management’s best estimate of the reasonably possible change in the amount of gross unrecognized tax benefits to be a decrease of approximately $1.9 million to a decrease of $2.9 million during the next twelve months mainly due to the expiration of certain statute of limitations, net of additions. The federal statute of limitations remains open for the years 2014 and forward. Tax years 2007 and forward are subject to audit by state tax authorities depending on the tax code and administrative practice of each state.