XML 79 R68.htm IDEA: XBRL DOCUMENT
v3.7.0.1

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016
Commitments And Contingencies Disclosure [Abstract] |  |  |  |
Total principal amount of loans repurchased or indemnified | $ 921 | $ 1,418 | $ 1,770 | $ 3,445

X
- Definition Principal amount of loans repurchased or indemnified during period. + References No definition available. + Details
Name: | fbk_PrincipalAmountOfLoansRepurchasedOrIndemnifiedDuringPeriod
Namespace Prefix: | fbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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