Loans (Narrative) (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016 USD ($) loan	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) loan	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, allowance percentage	0.91%		0.91%		0.93%
Total number of loans | loan	33		33		38
90 or greater days delinquent	$ 9,540,000		$ 9,540,000		$ 10,740,000
Total non-accrual loans	10,224,000		10,224,000		11,433,000
Deferred loan fees and premiums include net deferred fees paid by customers	2,600,000		2,600,000		2,600,000
Loan portfolio	1,005,068,000	$ 895,839,000	1,005,068,000	$ 895,839,000	918,894,000
Allowance for loan loss	9,106,000		9,106,000		8,540,000
Interest income recognized on outstanding TDR loans			253,000		508,000
Charge-offs	69,000	299,000	468,000	345,000
Loans, carrying amount	995,515,000		995,515,000		909,200,000
Non-accrual performing loans	684,000		684,000		693,000
Total Past Due	$ 10,361,000		$ 10,361,000		$ 11,688,000
Number of TDR loans | loan			24		30
Number of accrual TDR loans | loan	19		19		23
Financing receivable post modification recorded investment	$ 16,130,000		$ 16,130,000		$ 18,568,000
Accrual TDR loans	$ 10,878,000		$ 10,878,000		13,133,000
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, allowance percentage	80.00%		80.00%
Loan portfolio	$ 608,380,000	522,825,000	$ 608,380,000	522,825,000	$ 538,888,000
Percentage status of loan in portfolio	6.50%		6.50%		6.10%
Charge-offs				46,000
Total Past Due	$ 2,860,000		$ 2,860,000		$ 2,875,000
Number of TDR loans | loan			8		8
Financing receivable post modification recorded investment	9,715,000		$ 9,715,000		$ 9,839,000
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	57,167,000	63,480,000	57,167,000	63,480,000	67,246,000
Charge-offs	69,000	215,000	394,000	215,000
Total Past Due	1,071,000		$ 1,071,000		$ 1,499,000
Number of TDR loans | loan			7		8
Financing receivable post modification recorded investment	1,141,000		$ 1,141,000		$ 1,384,000
Commercial Equipment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	33,185,000	26,804,000	33,185,000	26,804,000	29,931,000
Charge-offs		54,000		54,000
Total Past Due	728,000		$ 728,000		$ 793,000
Number of TDR loans | loan			2		2
Financing receivable post modification recorded investment	118,000		$ 118,000		$ 123,000
Residential First Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Offset by net deferred premiums paid to purchase loans	2,200,000		2,200,000		1,400,000
Loan portfolio	148,138,000	137,439,000	148,138,000	137,439,000	131,401,000
Charge-offs		30,000		30,000
Total Past Due	1,258,000		$ 1,258,000		$ 2,247,000
Number of TDR loans | loan			2		3
Financing receivable post modification recorded investment	556,000		$ 556,000		$ 881,000
Adjustable Rate Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	$ 30,900,000		$ 30,900,000		$ 18,900,000
Percentage status of loan in portfolio	3.10%		3.10%		2.10%
Residential Rentals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	$ 100,202,000	$ 84,668,000	$ 100,202,000	$ 84,668,000	$ 93,157,000
Total Past Due	689,000		$ 689,000		$ 605,000
Number of TDR loans | loan			1		5
Financing receivable post modification recorded investment	230,000		$ 230,000		$ 2,058,000
1-4 Family Units [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	88,000,000		88,000,000		80,800,000
Apartment Buildings Rentals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	12,200,000		12,200,000		12,400,000
Nineteen Loans Representing Six Customer Relationships [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans with deferred collection of principal and interest for one year					3,800,000
Seventeen Loans Representing Six Customer Relationships [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans with deferred collection of principal and interest for one year	3,600,000		3,600,000
One Customer Relationship [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Reserve of the allowance for loan losses	470,000		470,000
Accrual TDR loans	8,100,000		8,100,000
Eight Loans With Two Construction And Land Development Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrual TDR loans	724,000		724,000
One Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrual TDR loans	197,000		197,000
Five Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrual TDR loans	7,100,000		7,100,000
Residential Development Project [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable post modification recorded investment	3,600,000		3,600,000		3,800,000
Three Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable post modification recorded investment	1,600,000		1,600,000		1,700,000
Financing Receivable Troubled Debt Restructuring [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans with deferred collection of principal and interest for one year	1,600,000		1,600,000		1,700,000
Seven Troubled Debt Restructuring Loans with Reserves [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			3,300,000
Specific reserves for TDR loans	968,000		$ 968,000
Number of TDR loans | loan			7
Nine Troubled Debt Restructuring Loans with Reserves [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment					3,600,000
Specific reserves for TDR loans					$ 1,300,000
Number of TDR loans | loan					9
Nonaccrual Loans With No Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total non-accrual loans	9,500,000		$ 9,500,000		$ 10,500,000
Interest due to debt			974,000		953,000
Nonaccrual Loans With Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total non-accrual loans	682,000		682,000		902,000
Interest due to debt			$ 83,000		34,000
Minimum [Member] | Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt maturity period			3 years
Minimum [Member] | Residential First Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt maturity period			10 years
Minimum [Member] | Residential Rentals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt maturity period			3 years
Maximum [Member] | Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt maturity period			20 years
Maximum [Member] | Residential First Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt maturity period			30 years
Maximum [Member] | Residential Rentals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt maturity period			20 years
Unrated [Member] | Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	50,104,000		$ 50,104,000		51,924,000
Unrated [Member] | Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	11,373,000		11,373,000		11,281,000
Unrated [Member] | Commercial Equipment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	10,137,000		10,137,000		10,074,000
Unrated [Member] | Residential Rentals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	23,209,000		23,209,000		21,585,000
Pass [Member] | Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	537,078,000		537,078,000		466,601,000
Pass [Member] | Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	41,789,000		41,789,000		51,569,000
Pass [Member] | Commercial Equipment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	22,752,000		22,752,000		19,610,000
Pass [Member] | Residential Rentals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	75,520,000		75,520,000		67,926,000
Special Mention [Member] | Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio					250,000
Special Mention [Member] | Residential Rentals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio					845,000
Substandard [Member] | Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	21,198,000		21,198,000		20,113,000
Substandard [Member] | Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	4,005,000		4,005,000		4,110,000
Substandard [Member] | Commercial Equipment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	159,000		159,000		110,000
Substandard [Member] | Residential Rentals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	1,473,000		1,473,000		2,801,000
Substandard [Member] | Nineteen Loans Representing Six Customer Relationships [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio					$ 8,100,000
Percentage status of loan in portfolio					71.00%
Substandard [Member] | Seventeen Loans Representing Six Customer Relationships [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	$ 7,700,000		$ 7,700,000
Percentage status of loan in portfolio	75.00%		75.00%
Doubtful [Member] | Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio					$ 286,000
Doubtful [Member] | Commercial Equipment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	$ 137,000		$ 137,000		137,000
Performing Financing Receivable [Member] | Residential First Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	$ 147,068,000		$ 147,068,000		129,453,000
Nonperforming Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase (decrease) in loans					$ 1,200,000
Percentage status of loan in portfolio	1.02%		1.02%		1.24%
Nonperforming Financing Receivable [Member] | Residential First Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan portfolio	$ 1,070,000		$ 1,070,000		$ 1,948,000
31 - 60 Days [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	110,000		110,000		217,000
31 - 60 Days [Member] | Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	41,000		41,000
31 - 60 Days [Member] | Commercial Equipment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due					152,000
61 - 89 Days [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	711,000		711,000		731,000
61 - 89 Days [Member] | Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	444,000		444,000
61 - 89 Days [Member] | Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due					138,000
61 - 89 Days [Member] | Commercial Equipment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	34,000		34,000		293,000
61 - 89 Days [Member] | Residential First Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	188,000		188,000		299,000
90 or Greater Days [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	9,540,000		9,540,000		10,740,000
90 or Greater Days [Member] | Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	2,416,000		2,416,000		2,875,000
90 or Greater Days [Member] | Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	1,030,000		1,030,000		1,361,000
90 or Greater Days [Member] | Commercial Equipment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	694,000		694,000		348,000
90 or Greater Days [Member] | Residential First Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	1,070,000		1,070,000		1,948,000
90 or Greater Days [Member] | Residential Rentals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Past Due	$ 689,000		$ 689,000		$ 605,000