Acquisitions and Divestitures (Tables)

12 Months Ended

Dec. 31, 2023

Business Combinations [Abstract]

Schedule of Selected Financial Information and Summary of Total Assets and Liabilities Relates to the Operations of Willis Re

The following selected financial information relates to the operations of Willis Re for the periods presented:

	Years ended December 31,
	2022			2021
Revenue from discontinued operations	$	48		$	721
Costs of providing services
Salaries and benefits		14			350
Other operating expenses		10			59
Depreciation and amortization		—			2
Transaction and transformation, net		—			33
Total costs of providing services		24			444
Other income, net		5			2
Income from discontinued operations before income taxes		29			279
(Loss)/gain on disposal of Willis Re		(65	)		2,300
Benefit from/(provision for) income tax expense		1			(500	)
Net income (payable to)/receivable from Gallagher on Deferred Closing		(5	)		1
(Loss)/income from discontinued operations, net of tax	$	(40	)	$	2,080