Discontinued Operations and Disposal Groups (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Discontinued Operations and Disposal Groups [Abstract]
Disposal Group, Including Discontinued Operation, Revenue	$ 766.5	$ 773.9	$ 1,506.6	$ 1,529.0
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents					$ 109.4
Disposal Group, Including Discontinued Operation, Costs of Goods Sold	629.1	593.7	1,244.5	1,198.0
Disposal Group, Including Discontinued Operation, Gross Profit (Loss)	137.4	180.2	262.1	331.0
Disposal Group, Including Discontinued Operation, General and Administrative Expense	85.4	53.6	184.1	95.7
Disposal Group, Including Discontinued Operation, Depreciation and Amortization	16.0	16.6	31.9	33.5
Disposal Group, Including Discontinued Operation, Restructuring and other charges	4.1	12.9	3.0	22.0
Disposal Group, Including Discontinued Operation, Operating Income (Loss)	31.9	97.1	43.1	179.8
Disposal Group, Including Discontinued Operation, Interest Expense	(0.5)	(0.2)	(0.5)	(0.3)
Disposal Group, Including Discontinued Operation, Interest Income	(0.5)	(0.3)	(1.2)	(0.6)
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax	40.2	116.3	45.6	204.8
Discontinued Operation, Tax Effect of Discontinued Operation	6.3	25.4	6.8	42.9
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	33.9	90.9	38.8	161.9
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	33.9	90.9	38.8	161.9
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net					436.5
Disposal Group, Including Discontinued Operation, Assets, Current	0.0		0.0		1,226.1
Disposal Group, Including Discontinued Operation, Prepaid and Other Assets, Current					96.6
Disposal Group, Including Discontinued Operation, Other Assets, Current					583.6
Disposal Group, Including Discontinued Operation, Goodwill, Noncurrent					1,997.3
Disposal Group, Including Discontinued Operation, Intangible Assets, Noncurrent					823.3
Disposal Group, Including Discontinued Operation, Assets					4,264.3
Disposal Group, Including Discontinued Operation, Deferred Tax Assets					1.2
Disposal Group, Including Discontinued Operation, Accounts Payable, Current					82.6
Disposal Group, Including Discontinued Operation, Accrued Liabilities, Current					281.8
Disposal Group, Including Discontinued Operation, Deferred Revenue, Current					271.5
Disposal Group, Including Discontinued Operation, Short-term operating lease liabilities					21.7
Disposal Group, Including Discontinued Operation, Liabilities, Current	0.0	657.6	0.0	657.6	657.6
Disposal Group, Including Discontinued Operation, Operating lease liabilities					26.8
Disposal Group, Including Discontinued Operation, Accrued Income Tax Payable, Noncurrent					192.8
Disposal Group, Including Discontinued Operation, Other Liabilities, Noncurrent					21.7
Disposal Group, Including Discontinued Operation, Liabilities					898.9
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment, Noncurrent					162.1
Disposal Group, Including Discontinued Operation, Other Assets, Noncurrent					54.3
Disposal Group, Including Discontinued Operation, Fortrea Senior Notes	$ 570.0		$ 570.0
Disposal Group, Including Discontinued Operation, Fortrea Senior Notes Interest Rate	7.50%		7.50%
Disposal Group, Including Discontinued Operation, Fortrea Distribution	$ 1,600.0		$ 1,600.0
Disposal Group, Including Discontinued Operation, Total Shareholders' Equity					3,365.4
Disposal Group, Including Discontinued Operation, Total liabilities and shareholders’ equity					$ 4,264.3
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	1,520.0		1,520.0
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	1,520.0		1,520.0
Disposal Group, Including Discontinued Operations, Other Nonoperating income (expense)	8.3	$ 19.1	4.2	$ 24.7
Fortrea Revolver due 2028
Discontinued Operations and Disposal Groups [Abstract]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	450.0		450.0
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	450.0		450.0
Fortrea Term Loan A maturing 2028
Discontinued Operations and Disposal Groups [Abstract]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	500.0		500.0
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	500.0		500.0
Fortrea Term Loan B maturing 2028
Discontinued Operations and Disposal Groups [Abstract]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	570.0		570.0
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Fortrea Credit Facilities	$ 570.0		$ 570.0