Assets and Liabilities of Business Held for Sale - Narrative (Details) $ in Billions	Dec. 31, 2019 USD ($)
Group Disability and Life \| Held-for-Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale price	$ 6.3

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration