Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Income Tax Disclosure [Abstract]

Provision (Benefit) for Income Taxes

The provision (benefit) for income taxes for the years ended December 31, 2019, 2018 and 2017, consisted of the following (in thousands):

	Years Ended December 31,
	2019		2018		2017
Current:
Federal	$	107,699	$	99,830	$	133,097
State	39,028		38,356		24,944
Foreign	33,227		35,007		27,079
Deferred:
Federal and state	(9,959)		$	(15,849)	$	41,717
Foreign	1,087		(30)		95
	$	171,082	$	157,314	$	226,932

Income Before Provision for Income Taxes

Income before the provision for income taxes for the years ended December 31, 2019, 2018 and 2017, consisted of the following (in thousands):

	Years Ended December 31,
	2019		2018		2017
Domestic	$	545,695	$	485,489	$	445,418
Foreign	79,820		106,113		72,098
	$	625,515	$	591,602	$	517,516

Difference of Income Taxes from Statutory Federal Income Tax Rates

The income taxes shown above varied from the statutory federal income tax rates for these periods as follows:

	Years Ended December 31,
	2019		2018		2017
Federal U.S. income tax rate	21.0	%	21.0	%	35.0	%
State income taxes, net of federal tax benefit	4.9		4.7		3.7
Permanent book/tax differences	1.1		0.6		0.4
Non-U.S. income taxed at different rates, net of foreign tax credits	2.1		2.0		—
Federal tax credits	(1.4)		(1.7)		(1.3)
Tax impact of uncertain tax positions	0.2		0.8		0.2
Tax effects of TCJA	—		0.4		6.5
Other, net	(0.5)		(1.2)		(0.6)
Effective tax rate	27.4	%	26.6	%	43.9	%

Deferred Portion of Tax Provision (Benefit)

The deferred portion of the tax (benefit) provision consisted of the following (in thousands):

	Years Ended December 31,
	2019		2018		2017
Accrued expenses, deducted for tax when paid	$	(17,797)	$	(21,884)	$	15,213
Capitalized costs for books, deducted for tax	3,246		(4,832)		(5,790)
Depreciation	3,526		10,071		(4,079)
Tax effects of TCJA	—		—		34,633
Other, net	2,153		766		1,835
	$	(8,872)	$	(15,879)	$	41,812

Components of Deferred Income Tax Amounts

The components of the deferred income tax amounts at December 31, 2019 and 2018, were as follows (in thousands):

	December 31,
	2019		2018
Deferred Income Tax Assets
Deferred compensation and other benefit obligations	$	105,096	$	87,513
Credits and net operating loss carryforwards	25,130		31,169
Stock-based compensation	7,805		9,535
Provision for bad debts	7,944		7,891
Workers’ compensation	3,929		3,580
Operating lease liabilities	51,932		—
Other	10,256		14,959
Total deferred income tax assets	212,092		154,647
Deferred Income Tax Liabilities
Amortization of intangible assets	(22,009)		(21,210)
Property and equipment basis differences	(16,981)		(9,761)
Right-of-use assets	(44,448)		—
Other	(7,278)		(10,319)
Total deferred income tax liabilities	(90,716)		(41,290)
Valuation allowance	(21,618)		(23,072)
Total deferred income tax assets, net	$	99,758	$	90,285

Reconciliation of Total Amounts of Gross Unrecognized Tax Benefits

The following table reconciles the total amounts of gross unrecognized tax benefits from January 1, 2017 to December 31, 2019 (in thousands): 

	December 31,
	2019		2018		2017
Balance at beginning of period	$	8,418	$	2,886	$	731
Gross increases—tax positions in prior years	—		3,259		1,503
Gross decreases—tax positions in prior years	(760)		(8)		(257)
Gross increases—tax positions in current year	1,703		2,284		956
Settlements	(4)		—		(40)
Lapse of statute of limitations	(3)		(3)		(7)
Balance at end of period	$	9,354	$	8,418	$	2,886