Certain Relationships and Related Transaction (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Related Party Transaction [Line Items]
Tax credit investments and investments in non-consolidated entities	$ 702	$ 156
CIT Group Inc. \| CIT Northbridge Credit LLC
Related Party Transaction [Line Items]
Equity method investment, ownership percentage	20.00%
Equity method investments	$ 31
Allstate Insurance Company and Subsidiary \| CIT Northbridge Credit LLC
Related Party Transaction [Line Items]
Noncontrolling interest, ownership percentage by parent	80.00%

Tax Credit Investment And Equity Method Investments

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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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.

+ References

No definition available.

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