Income taxes (Tables)

12 Months Ended

Dec. 31, 2020

Income Tax Disclosure [Abstract]

Provision (Benefit) for Income Taxes on Income from Continuing Operations

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

2020	Current		Deferred		Total
Federal	$	123,882	$	4,532	$	128,414
State and other	21,878		4,001		25,879
Total	$	145,760	$	8,533	$	154,293

2019	Current		Deferred		Total
Federal	$	59,791	$	21,345	$	81,136
State and other	7,567		719		8,286
Total	$	67,358	$	22,064	$	89,422

2018	Current		Deferred		Total
Federal	$	77,795	$	15,765	$	93,560
State and other	9,527		4,280		13,807
Total	$	87,322	$	20,045	$	107,367

Reconciliation of Effective Tax Rate

The provision for income taxes varies from the U.S. federal statutory tax rate as a result of the following differences:

	2020	2019	2018
U.S. statutory tax rate	21.0%	21.0%	21.0%
Increase (decrease) in taxes resulting from:
State taxes (net of federal income tax benefit)	3.3	3.1	2.9
Uncertain tax positions, settlements and lapse of statutes of limitations	(0.1)	(1.6)	(0.3)
Other valuation allowances, tax rate changes, & deferred adjustments	(0.1)	(1.7)	(1.0)
Valuation allowance on equity method investment	0.4	1.7	—
Enactment of the Tax Cuts and Jobs Act	—	—	(1.1)
Non-deductible transactions costs	—	0.3	—
Net excess benefits or expense on share-based payments	(0.1)	0.4	0.1
Other, net	(0.2)	0.6	(0.5)
Effective tax rate	24.2%	23.8%	21.1%

Deferred Tax Liabilities and Assets

Deferred tax liabilities and assets were composed of the following as of the end of December 31, 2020 and 2019 (in thousands):

	Dec. 31,
	2020		2019
Deferred tax liabilities
Accelerated depreciation	$	67,479	$	62,951
Accelerated amortization of deductible intangibles	536,740		524,697
Right-of-use assets for operating leases	24,220		25,615
Other	3,322		3,677
Total deferred tax liabilities	631,761		616,940
Deferred tax assets
Accrued compensation costs	18,559		16,180
Pension and post-retirement medical and life	25,523		35,192
Loss carryforwards	38,348		38,686
Operating lease liabilities	25,319		26,008
Other	37,239		30,914
Total deferred tax assets	144,988		146,980
Deferred tax asset valuation allowance	43,467		45,661
Total net deferred tax (liabilities)	$	(530,240)	$	(515,621)

The following table summarizes the activity related to deferred tax asset valuation allowances (in thousands):

	2020		2019		2018
Beginning at beginning of period	$	45,661	$	125,894	$	136,418
Additions to valuation allowance	3,719		9,545		3,908
Reductions to valuation allowance	(5,913)		(89,778)		(14,432)
Balance at the end of the period	$	43,467	$	45,661	$	125,894

Summary of Activity Related to Unrecognized Tax Benefits, Excluding Federal Tax Benefit of State Tax Deductions

The following table summarizes the activity related to unrecognized tax benefits, excluding the federal tax benefit of state tax deductions (in thousands):

	2020		2019		2018
Change in unrecognized tax benefits
Balance as of beginning of year	$	8,050	$	12,843	$	15,043
Additions based on tax positions related to the current year	—		—		40
Additions for tax positions of prior years	630		—		2,631
Reductions for tax positions of prior years	—		(959)		—
Settlements	—		(288)		(182)
Reductions due to lapse of statutes of limitations	(1,245)		(3,546)		(4,689)
Balance as of end of year	$	7,435	$	8,050	$	12,843