This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Expenses - Narrative (Details) - USD ($)	3 Months Ended		39 Months Ended
Expenses - Narrative (Details) - USD ($)	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2021
State Street Beacon
Restructuring Cost and Reserve [Line Items]
Restructuring accruals released	$ 4,000,000
Restructuring charges	(4,000,000)	$ 0
Charles River Development
Restructuring Cost and Reserve [Line Items]
Acquisitions costs	$ 13,000,000
Charles River Development \| Forecast
Restructuring Cost and Reserve [Line Items]
Acquisitions costs			$ 200,000,000