Loans (Narrative) (Details) (USD $)	Jun. 30, 2011	Dec. 31, 2010
Threshold at which impaired finance receivables that are placed on nonaccrual status are subject to individual review	$ 500,000
Consumer charge-offs, past due days, minimum	120
Consumer charge-offs, past due days, maximum	150
Commitments to lend additional funds to borrowers	39,500,000	19,600,000
Impaired Loans [Member]
Troubled debt restructuring	354,100,000	461,700,000
Corporate Finance [Member]
Percentage of investments in Troubled Debt Restructurings ("TDR")	75.00%	73.00%
Non Accrual [Member]
Threshold at which impaired finance receivables that are placed on nonaccrual status are subject to individual review		$ 500,000
Percentage of investments in Troubled Debt Restructurings ("TDR")	92.00%	95.00%

Reflects the amount related to a troubled debt restructuring.

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- Definition

Impaired finance receivables threshold for periodic individual review

+ Details

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- Definition

Maximum Due Days Before Consumer And Small Ticket Loans Accounts Are Charged Off

+ Details

Name:	cit_MaximumDueDaysBeforeConsumerAndSmallTicketLoansAccountsAreChargedOff
Namespace Prefix:	cit
Data Type:	xbrli:positiveIntegerItemType
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Period Type:	instant

- Definition

Minimum Due Days Before Consumer And Small Ticket Loans Accounts Are Charged Off

+ Details

Name:	cit_MinimumDueDaysBeforeConsumerAndSmallTicketLoansAccountsAreChargedOff
Namespace Prefix:	cit
Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage Of Investments In Troubled Debt Restructurings.

+ Details

Name:	cit_PercentageOfInvestmentsInTroubledDebtRestructurings
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- Definition

Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 15
-Paragraph 40
-Subparagraph b.

+ Details

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Period Type:	instant