Allowance for Loan Losses and Credit Quality of Loans, Impaired Loans (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Allowance for Loan Losses and Credit Quality of Loans [Abstract]
Minimum balance for classified loans to be evaluated individually for impairment	$ 500,000
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	31,868,000		31,440,000
Unpaid Principal Balance (Legal)	36,215,000		34,430,000
Related Allowance	925,000		715,000
Average Recorded Investment	32,294,000	23,732,000
Interest Income Recognized	132,000	156,000
Originated Loans [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	22,334,000	23,732,000
Interest Income Recognized	132,000	156,000
Acquired Loans [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	9,960,000	0
Interest Income Recognized	0	0
Commercial Loans [Member] | Business Banking [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	185,000	80,000
Interest Income Recognized	12,000	0
Commercial Loans [Member] | Originated Loans [Member] | Commercial [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	2,038,000	5,069,000
Interest Income Recognized	0	29,000
Commercial Loans [Member] | Originated Loans [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	11,553,000	12,339,000
Interest Income Recognized	42,000	72,000
Commercial Loans [Member] | Originated Loans [Member] | Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	125,000	378,000
Interest Income Recognized	0	3,000
Commercial Loans [Member] | Originated Loans [Member] | Agricultural Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,424,000	900,000
Interest Income Recognized	12,000	12,000
Commercial Loans [Member] | Acquired Loans [Member] | Commercial [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	6,436,000	0
Interest Income Recognized	0	0
Commercial Loans [Member] | Acquired Loans [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	3,524,000	0
Interest Income Recognized	0	0
Consumer Loans [Member] | Originated Loans [Member] | Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	4,282,000	2,901,000
Interest Income Recognized	43,000	29,000
Residential Real Estate Mortgages [Member] | Originated Loans [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	2,727,000	2,065,000
Interest Income Recognized	23,000	11,000
With No Allowance Recorded [Member] | Originated Loans [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	17,962,000		16,360,000
Unpaid Principal Balance (Legal)	19,945,000		18,173,000
With No Allowance Recorded [Member] | Commercial Loans [Member] | Originated Loans [Member] | Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	2,026,000		4,721,000
Unpaid Principal Balance (Legal)	2,096,000		4,777,000
With No Allowance Recorded [Member] | Commercial Loans [Member] | Originated Loans [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	7,252,000		4,613,000
Unpaid Principal Balance (Legal)	7,823,000		5,164,000
With No Allowance Recorded [Member] | Commercial Loans [Member] | Originated Loans [Member] | Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	124,000		125,000
Unpaid Principal Balance (Legal)	195,000		195,000
With No Allowance Recorded [Member] | Commercial Loans [Member] | Originated Loans [Member] | Agricultural Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	1,418,000		1,431,000
Unpaid Principal Balance (Legal)	1,697,000		1,708,000
With No Allowance Recorded [Member] | Commercial Loans [Member] | Originated Loans [Member] | Business Banking [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	172,000		210,000
Unpaid Principal Balance (Legal)	564,000		602,000
With No Allowance Recorded [Member] | Commercial Loans [Member] | Originated Loans [Member] | Total Commercial Loans [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	10,992,000		11,100,000
Unpaid Principal Balance (Legal)	12,375,000		12,446,000
With No Allowance Recorded [Member] | Commercial Loans [Member] | Acquired Loans [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	9,873,000		10,060,000
Unpaid Principal Balance (Legal)	10,380,000		10,380,000
With No Allowance Recorded [Member] | Commercial Loans [Member] | Acquired Loans [Member] | Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	6,380,000		6,501,000
Unpaid Principal Balance (Legal)	6,538,000		6,538,000
With No Allowance Recorded [Member] | Commercial Loans [Member] | Acquired Loans [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	3,493,000		3,559,000
Unpaid Principal Balance (Legal)	3,842,000		3,842,000
With No Allowance Recorded [Member] | Consumer Loans [Member] | Originated Loans [Member] | Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	4,248,000		3,248,000
Unpaid Principal Balance (Legal)	4,534,000		3,472,000
With No Allowance Recorded [Member] | Residential Real Estate Mortgages [Member] | Originated Loans [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	2,722,000		2,012,000
Unpaid Principal Balance (Legal)	3,036,000		2,255,000
With An Allowance Recorded [Member] | Commercial Loans [Member] | Originated Loans [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment Balance (Book)	4,033,000		5,020,000
Unpaid Principal Balance (Legal)	5,890,000		6,877,000
Related Allowance	$ 925,000		$ 715,000