Income Taxes

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Income Taxes

10.    Income Taxes

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Deferred tax liabilities (assets) are comprised of the following at December 31 (in thousands):

	2021			2020
Depreciation	$	165,405		$	153,573
Leases		27,876			29,036
Other		4,658			3,545
Gross deferred tax liabilities		197,939			186,154
Allowance for doubtful accounts		(1,374	)		(1,325	)
Equity-based compensation		(3,626	)		(3,059	)
Employee benefits		(8,516	)		(5,869	)
Leases		(27,357	)		(29,028	)
Claims and insurance		(27,351	)		(22,704	)
Other		(5,578	)		(4,351	)
Gross deferred tax assets		(73,802	)		(66,336	)
Net deferred tax liability	$	124,137		$	119,818

The Company has determined that a valuation allowance was not necessary at December 31, 2021 or 2020 for substantially all deferred tax assets since it is more likely than not they will be realized from future reversals of temporary differences or future taxable income.

The income tax provision for continuing operations consists of the following (in thousands):

	2021		2020		2019
Current:
U.S. federal	$	62,222	$	24,311	$	5,095
State		12,997		5,364		3,176
Total current income tax provision		75,219		29,675		8,271
Deferred:
U.S. federal		3,915		8,255		24,137
State		404		8		525
Total deferred income tax provision		4,319		8,263		24,662
Total income tax provision	$	79,538	$	37,938	$	32,933

A reconciliation between income taxes at the federal statutory rate (21 percent) and the effective income tax provision is as follows (in thousands):

	2021			2020			2019
Provision at federal statutory rate	$	69,856		$	37,018		$	30,797
State income taxes, net of federal benefit		11,435			5,664			5,106
Tax credits		(1,754	)		(1,424	)		(2,249	)
Excess tax benefit on stock compensation (1)		(793	)		(4,500	)		(1,471	)
Other, net		794			1,180			750
Total provision	$	79,538		$	37,938		$	32,933

(1) In accordance with ASC Topic 718, these excess tax benefits on stock compensation are reported as a financing cash flow, rather than as an operating cash flow.

The Company and its subsidiaries file income tax returns in the U.S. federal jurisdiction and various state jurisdictions. For the U.S. federal jurisdiction, tax years 2018-2021 remain open to examination. The expiration of the statute of limitations related to the various state income tax returns that the Company files varies by state. In general, tax years 2012-2021 remain open to examination by the various state and local jurisdictions. However, a state could challenge certain tax positions back to the 2008 tax year.

A reconciliation of the beginning and ending total amounts of gross unrecognized tax benefits is as follows (in thousands):

	2021			2020
Gross unrecognized tax benefits at beginning of year	$	1,052		$	957
Gross (decreases) increases in tax positions for prior years		(4	)		(2	)
Gross increases in tax positions for current year		598			236
Settlements		(96	)		—
Lapse of statute of limitations		(180	)		(139	)
Gross unrecognized tax benefits at end of year	$	1,370		$	1,052

The Company recognizes interest and penalties related to uncertain tax positions as a component of income tax expense. During the years ended December 31, 2021, 2020 and 2019, the Company did not record any interest related to unrecognized tax benefits. The Company had approximately $0.1 million and $0.1 million of accrued interest and penalties at December 31, 2021 and 2020, respectively. The total amount of unrecognized tax benefits, which is recorded within claims, insurance and other liabilities on the consolidated balance sheets, that would affect the Company’s effective tax rate if recognized is $1.4 million and $1.1 million as of December 31, 2021 and 2020, respectively. The Company paid cash for income taxes of $81.6 million, $10.0 million, and $15.0 million in 2021, 2020 and 2019, respectively.

The Company does not anticipate total unrecognized tax benefits will significantly change during the next twelve months due to the settlements of audits and the expiration of statutes of limitations.

In December 2019, U.S. federal tax law changes were enacted that reinstated the tax credits for alternative fuel usage for 2018 and 2019.  The Company recognized the tax credits of approximately $1.1 million in 2021 and $1.0 million in 2020.