Financial Data by Segment and Geographic Area (Tables)

12 Months Ended

Jun. 30, 2026

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment

The following tables present the Company's revenues, significant segment expenses, and earnings before income taxes by reportable segment:

Year ended June 30, 2026	Employer Services		PEO Services		Total
Revenues from external customers	$	13,476.9	$	7,115.7	$	20,592.6
Interest on funds held for clients	1,342.4		12.4		1,354.8
Intercompany revenues	12.1		—		12.1
Total segment revenues	14,831.4		7,128.1		21,959.5
Reconciliation of revenues:
Intercompany eliminations					(12.1)
Total consolidated revenues					$	21,947.4
Less segment expenses: (a)
Selling and marketing	2,365.7		415.6
Zero-margin benefits pass-through costs	—		4,607.3
Workers' compensation coverage and state unemployment taxes	—		718.4
Other segment expenses (b)	7,028.9		450.7
Total segment earnings before income taxes	5,436.8		936.1		6,372.9
Reconciliation of earnings before income taxes:
Other (c)					(642.6)
Total consolidated earnings before income taxes					$	5,730.3

Year ended June 30, 2025	Employer Services		PEO Services		Total
Revenues from external customers	$	12,692.2	$	6,679.6	$	19,371.8
Interest on funds held for clients	1,178.3		10.8		1,189.1
Intercompany revenues	12.6		—		12.6
Total segment revenues	13,883.1		6,690.4		20,573.5
Reconciliation of revenues:
Intercompany eliminations					(12.6)
Total consolidated revenues					$	20,560.9
Less segment expenses: (a)
Selling and marketing	2,177.1		362.8
Zero-margin benefits pass-through costs	—		4,289.0
Workers' compensation coverage and state unemployment taxes	—		681.3
Other segment expenses (b)	6,697.5		406.8
Total segment earnings before income taxes	5,008.5		950.5		5,959.0
Reconciliation of earnings before income taxes:
Other (c)					(648.9)
Total consolidated earnings before income taxes					$	5,310.1

Year ended June 30, 2024	Employer Services		PEO Services		Total
Revenues from external customers	$	11,953.6	$	6,224.3	$	18,177.9
Interest on funds held for clients	1,015.4		9.3		1,024.7
Intercompany revenues	11.8		—		11.8
Total segment revenues	12,980.8		6,233.6		19,214.4
Reconciliation of revenues:
Intercompany eliminations					(11.8)
Total consolidated revenues					$	19,202.6
Less segment expenses: (a)
Selling and marketing	2,025.0		330.5
Zero-margin benefits pass-through costs	—		3,975.9
Workers' compensation coverage and state unemployment taxes	—		613.4
Other segment expenses (b)	6,400.3		392.3
Total segment earnings before income taxes	4,555.5		921.5		5,477.0
Reconciliation of earnings before income taxes:
Other (c)					(604.7)
Total consolidated earnings before income taxes					$	4,872.3

(a) The significant expense categories and amounts align with the segment-level information that is regularly provided to the CODM. Intercompany expenses are included in the amounts shown.

(b) Other segment expenses for both reportable segments include operating, research and development, depreciation and amortization, and other general and administrative expenses.

(c) Other represents certain corporate overhead charges and expenses that have not been allocated to the reportable segments, including corporate functions, legal settlements, company-wide severance initiatives, non-recurring gains and losses, the elimination of intercompany transactions, and interest income and expense.

The following table presents the Company's depreciation and amortization included in earnings before income taxes for each reportable segment:

Years ended June 30,	2026		2025		2024
Employer Services	$	525.1	$	512.4	$	486.6
PEO Services	2.2		6.7		6.8
Other	58.6		63.3		68.5
Total depreciation and amortization	$	585.9	$	582.4	$	561.9

Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas

The following table presents the Company's revenues, which is based on the location of the billing entity, and assets by geographic area:

	United States		EMEA		Canada		Other		Total
Year ended June 30, 2026
Revenues	$	19,279.8	$	1,733.3	$	523.7	$	410.6	$	21,947.4
Assets	$	54,851.4	$	3,544.3	$	4,025.8	$	771.8	$	63,193.3
Year ended June 30, 2025
Revenues	$	18,179.2	$	1,533.5	$	489.3	$	358.9	$	20,560.9
Assets	$	46,763.0	$	3,025.5	$	2,750.7	$	830.1	$	53,369.3
Year ended June 30, 2024
Revenues	$	16,934.2	$	1,451.4	$	473.7	$	343.3	$	19,202.6
Assets	$	47,989.9	$	2,800.8	$	2,796.6	$	775.4	$	54,362.7