Acquisitions and Dispositions - Intangible asset by type (Details) - National General Holdings Corp. $ in Millions	Jan. 04, 2021 USD ($)
Business Acquisition [Line Items]
Intangible assets	$ 1,199
Distribution and customer relationships
Business Acquisition [Line Items]
Intangible assets	795
Trade names
Business Acquisition [Line Items]
Intangible assets	102
Licenses
Business Acquisition [Line Items]
Intangible assets	97
Technology
Business Acquisition [Line Items]
Intangible assets	$ 205

The amount of identifiable intangible assets recognized as of the acquisition date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=123455525&loc=d3e2207-128464

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123413009&loc=d3e4845-128472

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant