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Other Non-Interest Income and Expense (Narrative) (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Income and Expenses [Abstract]
Minimum percentage of the aggregate total net interest income and total non interest income required for amounts to be stated separately	1.00%cfr_MinimumPercentageOfAggregateNetInterestIncomeAndNonInterestIncomeRequiredForAmountsToBeStatedSeparately	1.00%cfr_MinimumPercentageOfAggregateNetInterestIncomeAndNonInterestIncomeRequiredForAmountsToBeStatedSeparately	1.00%cfr_MinimumPercentageOfAggregateNetInterestIncomeAndNonInterestIncomeRequiredForAmountsToBeStatedSeparately

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- Definition

Minimum Percentage Of Aggregate Net Interest Income And Non Interest Income Required For Amounts To Be Stated Separately

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No definition available.

+ Details

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- Details

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