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

FDIC Shared-Loss Receivable (Tables) | 6 Months Ended
--- | ---
Jun. 30, 2018
FDIC Shared-Loss Receivable [Abstract] |
Changes In Payable to FDIC |
| Three months ended June 30 |  | Six months ended June 30
(Dollars in thousands) | 2018 |  | 2017 |  | 2018 |  | 2017
Beginning balance | $ | 102,466 |  |  | $ | 98,013 |  |  | $ | 101,342 |  |  | $ | 97,008 |
Amortization | 1,001 |  |  | 963 |  |  | 1,993 |  |  | 1,917 |
Adjustments related to changes in assumptions | 20 |  |  | 150 |  |  | 152 |  |  | 201 |
Ending balance | $ | 103,487 |  |  | $ | 99,126 |  |  | $ | 103,487 |  |  | $ | 99,126 |

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