XML 73 R61.htm IDEA: XBRL DOCUMENT
v3.25.3

ALLOWANCE FOR LOAN AND LEASE LOSSES - Schedule of Allowance for Loan and Lease Losses (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Allowance for loan and lease losses, beginning balance | $ 1,672 | $ 1,700 | $ 1,676 | $ 1,747
Provision (benefit) for loan and lease losses | 214 | 123 | 473 | 311
Charge-offs | (256) | (177) | (567) | (464)
Recoveries | 22 | 32 | 70 | 84
Allowance for loan and lease losses, ending balance | 1,652 | 1,678 | 1,652 | 1,678
Commercial |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Allowance for loan and lease losses, beginning balance | 1,512 | 1,547 | 1,518 | 1,581
Provision (benefit) for loan and lease losses | 238 | 123 | 487 | 316
Charge-offs | (244) | (169) | (540) | (443)
Recoveries | 18 | 27 | 59 | 74
Allowance for loan and lease losses, ending balance | 1,524 | 1,528 | 1,524 | 1,528
Consumer |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Allowance for loan and lease losses, beginning balance | 160 | 153 | 158 | 166
Provision (benefit) for loan and lease losses | (24) | 0 | (14) | (5)
Charge-offs | (12) | (8) | (27) | (21)
Recoveries | 4 | 5 | 11 | 10
Allowance for loan and lease losses, ending balance | $ 128 | $ 150 | $ 128 | $ 150

X
- Definition Financing Receivable, Credit Loss, Expense + References No definition available. + Details
Name: | fcnca_FinancingReceivableCreditLossExpense
Namespace Prefix: | fcnca_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |