INCOME TAXES

Income tax expense consisted of the following (in thousands):



	Years Ended December 31,
	2016		2015		2014
Current:
Federal	$	237	$	32,090	$	51,260
State	2,928		5,665		6,606
Foreign	534		1,250		220
	3,699		39,005		58,086
Deferred:
Federal	42,895		33,912		4,503
State	1,737		4,530		535
	44,632		38,442		5,038
Total income tax expense	$	48,331	$	77,447	$	63,124

The effective income tax rate differs from the federal corporate tax rate of 35% in 2016, 2015 and 2014 as follows (in thousands):



	Years Ended December 31,
	2016			2015			2014
Tax at statutory rate	$	44,611		$	70,406		$	56,621
State income taxes, net of federal tax benefits	3,032			6,627			4,641
Non-deductible meals and entertainment	1,549			1,687			1,497
Income tax credits	(1,900		)	(1,700		)	(1,600		)
Other, net	1,039			427			1,965
Total income tax expense	$	48,331		$	77,447		$	63,124

At December 31, deferred tax assets and liabilities consisted of the following (in thousands):



	December 31,
	2016		2015
Deferred tax assets:
Insurance and claims accruals	$	74,015	$	71,285
Compensation-related accruals	10,056		10,187
Allowance for uncollectible accounts	6,135		6,138
Other	4,168		6,291
Gross deferred tax assets	94,374		93,901
Deferred tax liabilities:
Property and equipment	377,093		330,580
Prepaid expenses	7,737		7,229
Other	2,313		2,356
Gross deferred tax liabilities	387,143		340,165
Net deferred tax liability	$	292,769	$	246,264

Deferred tax assets are more likely than not to be realized as a result of historical profitability, future taxable income, and reversal of deferred tax liabilities.

We recognized a $1.1 million decrease in the net liability for unrecognized tax benefits for the year ended December 31, 2016 and a $0.6 million decrease for the year ended December 31, 2015. We accrued interest expense of $0.2 million during 2016 and $0.2 million during 2015, excluding from both years the reversal of accrued interest related to the adjustment of uncertain tax positions. If recognized, $3.9 million of unrecognized tax benefits as of December 31, 2016 and $5.0 million as of December 31, 2015 would impact our effective tax rate. Interest of $1.1 million as of December 31, 2016 and $1.4 million as of December 31, 2015 has been reflected as a component of the total liability. We expect no other significant increases or decreases for uncertain tax positions during the next twelve months. The reconciliations of beginning and ending gross balances of unrecognized tax benefits for 2016 and 2015 are shown below (in thousands).



	December 31,
	2016			2015
Unrecognized tax benefits, beginning balance	$	7,717		$	8,583
Gross increases – tax positions in prior period	236			229
Gross decreases – tax positions in prior period	(217		)	—
Gross increases – current-period tax positions	473			769
Settlements	(2,154		)	(1,864		)
Unrecognized tax benefits, ending balance	$	6,055		$	7,717

We file U.S. federal income tax returns, as well as income tax returns in various states and several foreign jurisdictions. The years 2013 through 2015 are open for examination by the U.S. Internal Revenue Service (“IRS”), and various years are open for examination by state and foreign tax authorities. In fourth quarter 2016, the IRS completed its audit of our amended 2011 federal income tax return with no additional taxes or penalties due. State and foreign jurisdictional statutes of limitations generally range from three to four years.