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    <Log type="Info">Element fcnca_UnrealizedLossesRelatedToMarketabilityOfSecuritiesOrIssuersAbilityToHonorRedemptionObligations had a mix of decimals attribute values: -3 0.</Log>
    <Log type="Info">Element us-gaap_AmortizationOfMortgageServicingRightsMSRs had a mix of decimals attribute values: -5 -3.</Log>
    <Log type="Info">Element us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued had a mix of decimals attribute values: 0 2.</Log>
    <Log type="Info">Element us-gaap_BusinessCombinationAcquisitionRelatedCosts had a mix of decimals attribute values: -5 -3.</Log>
    <Log type="Info">Element us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations had a mix of decimals attribute values: 2 4.</Log>
    <Log type="Info">Element us-gaap_ImpairmentOfInvestments had a mix of decimals attribute values: -3 0.</Log>
    <Log type="Info">Element us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity had a mix of decimals attribute values: -7 -5.</Log>
    <Log type="Info">Element us-gaap_OtherRealEstateAdditions had a mix of decimals attribute values: -5 -3.</Log>
    <Log type="Info">Element us-gaap_OtherRealEstateCoveredAdditions had a mix of decimals attribute values: -5 -3.</Log>
    <Log type="Info">Element us-gaap_OtherRealEstateNonCoveredAdditions had a mix of decimals attribute values: -5 -3.</Log>
    <Log type="Info">'Monetary' elements on report '2401402 - Disclosure - Accounting Policies and Basis of Presentation Summary of Significant Accounting Policies (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2402404 - Disclosure - Business Combinations Businss Combinations (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2403402 - Disclosure - Investments (Aggregate Values and Unrealized Gains and Losses) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2403406 - Disclosure - Investments (Narrative) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2404403 - Disclosure - Loans and Leases (Narrative) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2404404 - Disclosure - Loans and Leases (Loans and Leases Outstanding) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2405403 - Disclosure - Allowance for Loan and Lease Losses (Allocation of Allowance for Loan and Lease Losses) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2405404 - Disclosure - Allowance for Loan and Lease Losses (Troubled Debt Restructuring) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2406403 - Disclosure - Premises and Equipment (Operating Leases) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2411402 - Disclosure - Short-Term Borrowings (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2412402 - Disclosure - Long-Term Obligations (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2414402 - Disclosure - Employee Benefit Plans (Narrative) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2414408 - Disclosure - Employee Benefit Plans (Projected Benefit Payments) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2415402 - Disclosure - Other Noninterest Income and Other Noninterest Expense (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2417402 - Disclosure - Transactions with Related Persons (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2419402 - Disclosure - Goodwill and Intangible Assets (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2420402 - Disclosure - Shareholders' Equity, Dividends Restrictions and Other Regulatory Matters (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2421401 - Disclosure - Commitments and Contingencies (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2424402 - Disclosure - Parent Company Financial Statements (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">Process Flow-Through: 1001000 - Statement - Consolidated Balance Sheets</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2011'</Log>
    <Log type="Info">Process Flow-Through: 1001501 - Statement - Consolidated Balance Sheets (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 1002000 - Statement - Consolidated Statements of Income</Log>
    <Log type="Info">Process Flow-Through: 1003000 - Statement - Consolidated Statement of Comprehensive Income</Log>
    <Log type="Info">Process Flow-Through: 1004501 - Statement - Consolidated Statements of Changes In Shareholders' Equity (Parenthetical)</Log>
    <Log type="Info">	Process Flow-Through: Removing column '12 Months Ended
Dec. 31, 2013'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '12 Months Ended
Dec. 31, 2012'</Log>
    <Log type="Info">Process Flow-Through: 1005000 - Statement - Consolidated Statements of Cash Flows</Log>
  </Logs>
  <InputFiles>
    <File>fcnca-20141231.xml</File>
    <File>fcnca-20141231.xsd</File>
    <File>fcnca-20141231_cal.xml</File>
    <File>fcnca-20141231_def.xml</File>
    <File>fcnca-20141231_lab.xml</File>
    <File>fcnca-20141231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles />
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
