Certain Relationships And Related Transactions (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Related Party Transaction [Line Items]
Investment in joint venture	$ 247.6	$ 220.2
Other assets	$ 1,595.5	2,117.0
Strategic Credit Partners Holdings LLC
Related Party Transaction [Line Items]
Equity interest percentage	10.00%
Investment in joint venture	$ 7.3	5.4
Strategic Credit Partners Holdings LLC \| Loans
Related Party Transaction [Line Items]
Loans sold in joint venture	$ 241.1
CIT Northbridge
Related Party Transaction [Line Items]
Equity interest percentage	20.00%
Equity interest percentage owned by other investors	80.00%
Equity investment	$ 5.0
Investments In Non-Consolidated Entities
Related Party Transaction [Line Items]
Other assets	$ 248.0	$ 220.0

Equity Method Investment, Ownership Percentage by Other Investors

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

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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.

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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Amount of assets classified as other.

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Amount of transactions with related party during the financial reporting period.

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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.

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