Income Taxes

3 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Income Tax Disclosure [Text Block]

Income Taxes The reconciliation between the U.S. federal statutory income tax rate and the effective income tax rate is presented below.

	Three months ended
	December 31,
	2021		2020
U.S. federal statutory income tax rate	21.0	%	21.0	%
Adjustments to reconcile to the effective tax rate:
State income taxes, net of federal benefit	3.9		4.5
Excess tax benefits related to stock-based compensation	(1.0)		(0.6)
Tax credits	(1.2)		(1.4)
Global Intangible Low-Taxed Income	0.3		0.6
Foreign income tax rate differential	(0.7)		(0.9)
Valuation allowances	1.4		1.5
Other	0.5		1.1
Effective income tax rate	24.2	%	25.8	%

At December 31, 2021 and September 30, 2021, the gross liabilities for unrecognized income tax benefits were $4.6 million and $4.8 million, respectively,

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

The reconciliation between the U.S. federal statutory income tax rate and the effective income tax rate is presented below.

	Three months ended
	December 31,
	2021		2020
U.S. federal statutory income tax rate	21.0	%	21.0	%
Adjustments to reconcile to the effective tax rate:
State income taxes, net of federal benefit	3.9		4.5
Excess tax benefits related to stock-based compensation	(1.0)		(0.6)
Tax credits	(1.2)		(1.4)
Global Intangible Low-Taxed Income	0.3		0.6
Foreign income tax rate differential	(0.7)		(0.9)
Valuation allowances	1.4		1.5
Other	0.5		1.1
Effective income tax rate	24.2	%	25.8	%