Consolidated Statements of Stockholders' Equity (Parenthetical) (unaudited) - $ / shares shares in Thousands	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Consolidated Statements of Stockholders' Equity
Shares issued in the acquisition of CNB and FNBNY Bancorp for 2015 and 2014 respectively (in shares)	5,647,268	240,598
Cash dividend declared (in dollars per share)	$ 0.69	$ 0.69

Number of shares of stock issued during the period pursuant to acquisitions.

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 FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28,29)

-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 02

-Paragraph 29, 30

-Article 5

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration