Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Income Tax Disclosure [Abstract]

Schedule of Components of Provision For Income Taxes

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

	2020		2019		2018
Currently payable:
Federal	$	67,606,617	$	73,563,685	$	83,010,387
State	10,180,218		3,765,929		3,743,781
Foreign	1,882,195		1,468,018		1,776,837
Total	79,669,030		78,797,632		88,531,005
Deferred income tax benefit:
Primarily federal	(15,419,722)		(3,066,237)		(4,367,155)
Provision for income taxes	$	64,249,308	$	75,731,395	$	84,163,850

Schedule of Effective Income Tax Rates Different From Statutory Federal Income Tax Rates

The effective income tax rates are different from the statutory federal income tax rates for the following reasons:

	2020		2019		2018
Statutory federal income tax rate	21.0	%	21.0	%	21.0	%
State income taxes, net of federal income tax benefit	2.1		0.6		0.6
Research tax credit	(1.4)		(1.1)		(0.8)
(Decrease) Increase in reserve for uncertain tax provisions	(0.1)		0.3		0.1
Change in tax rate on deferred taxes	—		—		0.5
Foreign tax credit	(0.1)		(0.1)		(0.1)
Foreign derived intangible income deduction	(5.2)		(4.8)		(4.6)
Stock compensation	(1.0)		(1.1)		(1.0)
Other	0.3		0.3		0.4
Effective income tax rate	15.6	%	15.1	%	16.1	%

Schedule of Deferred Income Tax Assets And Liabilities

The tax effect of temporary differences which give rise to deferred income tax assets and liabilities at    December 31, 2020 and 2019, are as follows: 

	December 31,
	2020		2019
Assets:
Accruals not currently deductible	$	13,135,048	$	6,478,146
Stock based compensation	11,983,900		9,100,745
Other	1,163,204		66,830
Total deferred income tax assets	$	26,282,152	$	15,645,721
Liabilities:
Excess tax over book depreciation	$	(16,606,068)	$	(30,725,471)
Goodwill	(33,427,901)		(27,799,640)
Intangible assets	(11,237,588)		(6,171,628)
Other	(3,971,338)		(2,403,131)
Total deferred income tax liability	$	(65,242,895)	$	(67,099,870)
Net deferred income taxes	$	(38,960,743)	$	(51,454,149)

Schedule of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:

	2020		2019		2018
Beginning of year	$	6,392,000	$	4,678,000	$	4,435,000
Additions based on tax positions related to the current year	918,000		1,695,000		1,677,000
Additions for tax positions in prior years	770,000		657,000		283,000
Reductions for tax positions in prior years	(2,907,000)		(38,000)		(163,000)
Reductions as a result of completed audit examinations	—		—		(1,554,000)
Reductions as a result of a lapse of the applicable statute of limitations	(309,000)		(600,000)		—
End of year	$	4,864,000	$	6,392,000	$	4,678,000