XML 73 R63.htm IDEA: XBRL DOCUMENT
v3.22.2

Investment Securities - Narrative (Details) shares in Thousands, $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2022 USD ($) security shares | Jun. 30, 2021 USD ($) | Jun. 30, 2022 USD ($) security shares | Jun. 30, 2021 USD ($) | Dec. 31, 2021 USD ($)
Schedule of Investments [Line Items] |  |  |  |  |
Debt securities, available-for-sale, accrued Interest | $ 25.0 |  | $ 25.0 |  | $ 22.0
Debt Securities, held-to-maturity, accrued interest | 17.0 |  | 17.0 |  | 7.0
Write off of accrued interest receivable | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.0 |
Debt securities, held-to-maturity, threshold period past due | 30 days |  | 30 days |  |
Securities past due | $ 9,832.0 |  | $ 9,832.0 |  | 3,809.0
Held-to-maturity securities, nonaccrual | 0.0 |  | 0.0 |  | 0.0
Federal Home Loan Bank stock | 83.0 |  | 83.0 |  | 40.0
Non-marketable equity securities | 69.0 |  | 69.0 |  | 10.0
Amortization method qualified affordable housing project investments | 538.0 |  | 538.0 |  | 156.0
Asset Pledged as Collateral |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Investment securities, aggregate carrying value, pledged as collateral | $ 5,200.0 |  | $ 5,200.0 |  | $ 5,700.0
Visa, Inc | Class B Common Stock |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Investment owned (in shares) | shares | 354 |  | 354 |  |
Residential Mortgage Backed Securities or Government Agency Securities |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, number of positions | security | 53 |  | 53 |  |

X
- Definition Debt Securities, Write Off Of Accrued Interest Receivable + References No definition available. + Details
Name: | fcnca_DebtSecuritiesWriteOffOfAccruedInterestReceivable
Namespace Prefix: | fcnca_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of investment in qualified affordable housing projects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
Name: | us-gaap_AmortizationMethodQualifiedAffordableHousingProjectInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 3A -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL120267853-210455 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2A -URI https://asc.fasb.org/extlink&oid=126970911&loc=SL121698322-111563 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 3B -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL120267856-210455 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleAndHeldToMaturity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922888-210455 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5C -URI https://asc.fasb.org/extlink&oid=126970911&loc=SL121698325-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=124255206&loc=SL120267845-210446 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 3A -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL120267960-210447 + Details
Name: | us-gaap_DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount excluding accrued interest, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 3B -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL120267963-210447 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 + Details
Name: | us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investment in debt security measured at amortized cost (held-to-maturity) on nonaccrual status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447 + Details
Name: | us-gaap_DebtSecuritiesHeldToMaturityNonaccrual
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Threshold period for when investment in debt security measured at amortized cost (held-to-maturity) is considered past due, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes threshold period past due to write off as uncollectible. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 14 -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447 + Details
Name: | us-gaap_DebtSecuritiesHeldToMaturityThresholdPeriodPastDue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126980263&loc=SL75117539-209714 + Details
Name: | us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 325 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=123599499&loc=d3e63345-112809 + Details
Name: | us-gaap_FederalHomeLoanBankStock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Balance held at close of period in number of shares. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section 50 -Paragraph 6 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column B)) -URI https://asc.fasb.org/extlink&oid=122147990&loc=d3e611197-123010 + Details
Name: | us-gaap_InvestmentOwnedBalanceShares
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_ScheduleOfInvestmentsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_PledgedStatusAxis=us-gaap_AssetPledgedAsCollateralMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=fcnca_VisaIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_USTreasuryAndGovernmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |