XML 60 R7.htm IDEA: XBRL DOCUMENT
v3.3.0.814

Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical) - $ / shares | 9 Months Ended
--- | ---
Sep. 30, 2015 | Sep. 30, 2014
Common stock dividends per share, declared | $ 0.60 | $ 0.57
Series A 3% Preferred Stock [Member] |  |
Preferred stock dividends per share, declared | $ 2.25 | $ 2.25
Preferred stock, dividend percentage | 3.00% | 3.00%
Series B-1 8.48% Preferred Stock [Member] |  |
Preferred stock dividends per share, declared | $ 6.36 | $ 6.36
Preferred stock, dividend percentage | 8.48% | 8.48%

X
- Definition Aggregate dividends declared during the period for each share of common stock outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 + Details
Name: | us-gaap_CommonStockDividendsPerShareDeclared
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The percentage rate used to calculate dividend payments on preferred stock. + References No definition available. + Details
Name: | us-gaap_PreferredStockDividendRatePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Aggregate dividends declared during the period for each share of preferred stock outstanding. + References No definition available. + Details
Name: | us-gaap_PreferredStockDividendsPerShareDeclared
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=fisi_Series3PreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesBPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |