Certain Relationships and Related Transactions (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Related Party Transaction [Line Items]
Other assets	$ 1,667.1	$ 2,117.0
Investments In Non-Consolidated Entities
Related Party Transaction [Line Items]
Other assets	266.0	220.0
Strategic Credit Partners Holdings LLC
Related Party Transaction [Line Items]
Loans sold in joint venture	$ 241.1
Equity interest percentage	10.00%
Equity investment	$ 7.5	$ 5.4
CIT Northbridge
Related Party Transaction [Line Items]
Equity interest percentage	20.00%
Equity interest percentage by other owners	80.00%
Equity investment	$ 1.0

Equity Method Investment, Ownership Percentage by Other Investors

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
-Topic 210
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-Paragraph 1
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- Definition

The face amount of loans that will be sold to other entities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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- Definition

Amount of assets classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 942
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- Definition

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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