Note 4. Income Taxes

The components of the provision for income taxes are as follows:



	Year Ended December 31,
(In thousands)	2015		2014		2013
Current:
Federal	$	120,437	$	123,598	$	74,202
State	21,248		15,858		15,635
	141,685		139,456		89,837
Deferred:
Federal	38,549		21,542		28,593
State	5,093		4,002		4,143
	43,642		25,544		32,736
Total provision for income taxes	$	185,327	$	165,000	$	122,573

The following is a reconciliation of income tax expense calculated using the U.S. statutory federal income tax rate with our income tax expense for 2015, 2014 and 2013:



	Year Ended December 31,
(In thousands)	2015			2014			2013
Tax provision at statutory rate	$	171,506		$	151,380		$	115,040
State income taxes, net of federal benefit	17,097			14,120			12,083
Meals and entertainment disallowance	1,035			959			872
Tax credits	(3,036		)	(1,307		)	(5,422		)
Other, net	(1,275		)	(152		)	—
Total provision for income taxes	$	185,327		$	165,000		$	122,573

Deferred tax assets and liabilities consist of the following:



	December 31,
(In thousands)	2015			2014
Deferred tax assets:
Claims and insurance reserves	$	41,576		$	36,690
Allowance for doubtful accounts	1,730			2,161
Accrued vacation	22,174			19,291
Deferred compensation	33,382			28,648
Other	12,008			12,924
Total deferred tax assets	110,870			99,714
Valuation allowance	—			(559		)
Net deferred tax assets	110,870			99,155
Deferred tax liabilities:
Depreciation and amortization	(334,379		)	(279,324		)
Unrecognized revenue	(10,062		)	(9,506		)
Other	(1,483		)	(1,737		)
Total deferred tax liabilities	(345,924		)	(290,567		)
Net deferred tax liability	$	(235,054	)	$	(191,412	)

As of December 31, 2015, the Company had various state tax credit carryforwards of approximately $4.2 million that are scheduled to expire in one to fifteen years.

We are subject to U.S. federal income tax, as well as income tax of multiple state tax jurisdictions. We remain open to examination by the Internal Revenue Service for tax years 2012 through 2015. We remain open to examination by various state tax jurisdictions for tax years 2011 through 2015.

The Company's liability for unrecognized tax benefits was immaterial as of December 31, 2015 and 2014. Interest and penalties related to uncertain tax positions, which are immaterial, are recorded in our Provision for Income Taxes on our Statements of Operations. Changes in our liability for unrecognized tax benefits could affect our effective tax rate, if recognized, but we do not expect any material changes within the next twelve months.