XML 38 R27.htm IDEA: XBRL DOCUMENT
v3.10.0.1

FDIC Shared-Loss Receivable (Tables) | 9 Months Ended
--- | ---
Sep. 30, 2018
FDIC Shared-Loss Receivable [Abstract] |
Changes In Payable to FDIC | The following table provides changes in the FDIC shared-loss payable for the three and nine months ended September 30, 2018 and September 30, 2017.
| Three months ended September 30 |  | Nine months ended September 30
(Dollars in thousands) | 2018 |  | 2017 |  | 2018 |  | 2017
Beginning balance | $ | 103,487 |  |  | $ | 99,126 |  |  | $ | 101,342 |  |  | $ | 97,008 |
Amortization | 1,009 |  |  | 973 |  |  | 3,002 |  |  | 2,890 |
Adjustments related to changes in assumptions | 80 |  |  | 104 |  |  | 232 |  |  | 305 |
Ending balance | $ | 104,576 |  |  | $ | 100,203 |  |  | $ | 104,576 |  |  | $ | 100,203 |

X
- Definition FDIC Shared-Loss Receivable [Abstract] + References No definition available. + Details
Name: | fcnca_FDICSharedLossReceivableAbstract
Namespace Prefix: | fcnca_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition [Table Text Block] for Schedule For FDIC Share-Loss Payable + References No definition available. + Details
Name: | fcnca_ScheduleForFDICShareLossPayableTableTextBlock
Namespace Prefix: | fcnca_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration