XML 133 R117.htm IDEA: XBRL DOCUMENT v2.4.1.9

Segment Reporting (Business Segment Assets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014 segment		Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Goodwill	$ 61,153us-gaap_Goodwill		$ 48,536us-gaap_Goodwill	$ 48,536us-gaap_Goodwill
Other intangible assets, net	7,486us-gaap_FiniteLivedIntangibleAssetsNet
Assets	3,089,521us-gaap_Assets	[1]	2,928,636us-gaap_Assets
Number of operating segments	2us-gaap_NumberOfOperatingSegments
Banking [Member]
Segment Reporting Information [Line Items]
Goodwill	48,536us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = fisi_BankingSegmentMember
Other intangible assets, net	1,125us-gaap_FiniteLivedIntangibleAssetsNet / us-gaap_StatementBusinessSegmentsAxis = fisi_BankingSegmentMember
Assets	3,065,109us-gaap_Assets / us-gaap_StatementBusinessSegmentsAxis = fisi_BankingSegmentMember	[1]
Insurance [Member]
Segment Reporting Information [Line Items]
Goodwill	12,617us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = fisi_InsuranceSegmentMember
Other intangible assets, net	6,361us-gaap_FiniteLivedIntangibleAssetsNet / us-gaap_StatementBusinessSegmentsAxis = fisi_InsuranceSegmentMember
Assets	20,368us-gaap_Assets / us-gaap_StatementBusinessSegmentsAxis = fisi_InsuranceSegmentMember	[1]
Holding Company and Other [Member]
Segment Reporting Information [Line Items]
Assets	$ 4,044us-gaap_Assets / us-gaap_StatementBusinessSegmentsAxis = fisi_HoldingCompanyAndOtherSegmentMember	[1]
[1] Reflects activity from SDN since August 1, 2014, the date of acquisition.

X

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.18)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 18

-Article 5

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X

- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267



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X

- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

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