Summary of Significant Accounting Policies - Narrative (Details) € in Millions, $ in Millions	Dec. 31, 2021 EUR (€)	Dec. 31, 2021 USD ($)	Apr. 01, 2021 EUR (€)	Apr. 01, 2021 USD ($)	Oct. 01, 2020 USD ($)
HPS Business | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Transaction consideration			€ 468	$ 551
Cash held relating to customer deposit liabilities				$ 34
HHS Business | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Transaction consideration					$ 5,000
Cash held relating to customer deposit liabilities					$ 8
FDB Business | Disposal Group, Held-for-sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Transaction consideration	€ 300	$ 340
Cash held relating to customer deposit liabilities		$ 670