XML 49 R38.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Investments (Unrealized Losses) (Details) - USD ($) | Sep. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Schedule of Investments [Line Items] |  |
Unrealized losses related to marketability of securities or issuer's ability to honor redemption obligations | $ 0 |
Investment securities available for sale: |  |
Fair Value, Less than 12 months | 2,846,381,000 | 3,752,642,000
Unrealized Losses, Less than 12 months | 29,397,000 | 21,458,000
Fair Value, 12 months or more | 1,516,296,000 | 2,975,631,000
Unrealized Losses, Greater than 12 months | 60,586,000 | 59,470,000
Fair Value, Total | 4,362,677,000 | 6,728,273,000
Unrealized Losses, Total | 89,983,000 | 80,928,000
U. S. Treasury |  |
Investment securities available for sale: |  |
Fair Value, Less than 12 months | 1,495,438,000 | 1,408,166,000
Unrealized Losses, Less than 12 months | 3,996,000 | 345,000
Fair Value, 12 months or more | 9,996,000 | 249,698,000
Unrealized Losses, Greater than 12 months | 2,000 | 201,000
Fair Value, Total | 1,505,434,000 | 1,657,864,000
Unrealized Losses, Total | 3,998,000 | 546,000
Government Agency |  |
Investment securities available for sale: |  |
Fair Value, Less than 12 months | 103,883,000 | 848,000
Unrealized Losses, Less than 12 months | 432,000 | 12,000
Fair Value, 12 months or more | 2,707,000 | 2,527,000
Unrealized Losses, Greater than 12 months | 42,000 | 28,000
Fair Value, Total | 106,590,000 | 3,375,000
Unrealized Losses, Total | 474,000 | 40,000
Mortgage Backed Securities |  |
Investment securities available for sale: |  |
Fair Value, Less than 12 months | 1,228,345,000 | 2,333,254,000
Unrealized Losses, Less than 12 months | 24,796,000 | 20,911,000
Fair Value, 12 months or more | 1,498,593,000 | 2,723,406,000
Unrealized Losses, Greater than 12 months | 60,518,000 | 59,241,000
Fair Value, Total | 2,726,938,000 | 5,056,660,000
Unrealized Losses, Total | 85,314,000 | 80,152,000
Investment securities held to maturity |  |
Fair Value, Less than 12 months | 2,124,316,000 |
Unrealized Losses, Less than 12 months | 14,907,000 |
Fair Value, 12 months or more | 10,549,000 |
Unrealized Losses, 12 months or more | 286,000 |
Fair Value, Total | 2,134,865,000 |
Unrealized Losses, Total | 15,193,000 | 0
Corporate bonds |  |
Investment securities available for sale: |  |
Fair Value, Less than 12 months |  | 5,025,000
Unrealized Losses, Less than 12 months |  | 8,000
Fair Value, 12 months or more |  | 0
Unrealized Losses, Greater than 12 months |  | 0
Fair Value, Total |  | 5,025,000
Unrealized Losses, Total |  | 8,000
Equity Securities |  |
Investment securities available for sale: |  |
Unrealized Losses, Total |  | 0
Corporate Bonds |  |
Investment securities available for sale: |  |
Fair Value, Less than 12 months | 18,715,000 |
Unrealized Losses, Less than 12 months | 173,000 |
Fair Value, 12 months or more | 5,000,000 |
Unrealized Losses, Greater than 12 months | 24,000 |
Fair Value, Total | 23,715,000 |
Unrealized Losses, Total | 197,000 | 8,000
Other |  |
Investment securities available for sale: |  |
Fair Value, Less than 12 months |  | 5,349,000
Unrealized Losses, Less than 12 months |  | 182,000
Fair Value, 12 months or more |  | 0
Unrealized Losses, Greater than 12 months |  | 0
Fair Value, Total |  | 5,349,000
Unrealized Losses, Total | $ 0 | $ 182,000

X
- Definition Unrealized Losses Related to Marketability of Securities or Issuer's Ability to Honor Redemption Obligations + References No definition available. + Details
Name: | fcnca_UnrealizedLossesRelatedtoMarketabilityofSecuritiesorIssuersAbilitytoHonorRedemptionObligations
Namespace Prefix: | fcnca_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

X
- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for less than 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for less than 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for 12 months or longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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_InvestmentTypeAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

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

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

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