XML 58 R44.htm IDEA: XBRL DOCUMENT
v3.25.4

OTHER SECURITIES (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2025
Banking and Thrift, Interest [Abstract] |
Schedule of Other Securities | Following is a summary of non-marketable equity securities: TABLE 4.1
December 31 | 2025 |  | 2024
(in millions) |  |  |
Federal Home Loan Bank stock | $ | 190 |  |  | $ | 187 |
Federal Reserve Bank stock | 142 |  |  | 142 |
Other non-marketable equity securities | 1 |  |  | 1 |
Total non-marketable equity securities | $ | 333 |  |  | $ | 330 |

X
- Definition Schedule of Other Securities [Table Text Block] + References No definition available. + Details
Name: | fnb_ScheduleofOtherSecuritiesTableTextBlock
Namespace Prefix: | fnb_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

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