Loans Receivable, Non-Performing Assets and Impaired Loans (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	$ 18,736,000	$ 19,856,000
Impaired Loans with Specific Allowance, Related Allowance	2,777,000	3,303,000
Impaired Loans with No Specific Allowance, Recorded Investment	23,355,000	26,032,000
Total Impaired Loans, Recorded Investment	42,091,000	45,888,000
Total Impaired Loans, Unpaid Principal Balance	44,199,000	51,302,000
Impaired Loans with Specific Allowance, Average Recorded Investment	19,467,000	27,085,000
Impaired Loans with Specific Allowance, Interest Income Recognized	745,000	1,178,000
Impaired Loans with No Specific Allowance, Average Recorded Investment	28,658,000	45,838,000
Impaired Loans with No Related Allowance, Interest Income Recognized	1,150,000	1,816,000
Total Impaired Loans, Average Recorded Investment	48,125,000	72,923,000
Total Impaired Loans Interest Income Recognized	1,895,000	2,994,000
Loans in nonaccrual status included in impaired loans	29,301,000svbi_LoansThatAreNotInNonAccrualStatus
Impaired loans	42,091,000	45,888,000
Total loans	681,959,000	650,752,000
Pass [Member]
Impaired loans [Abstract]
Total loans	642,479,000	607,777,000
Residential Mortgage [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	14,094,000	16,910,000
Impaired Loans with Specific Allowance, Related Allowance	2,113,000	2,749,000
Impaired Loans with No Specific Allowance, Recorded Investment	14,441,000	18,154,000
Total Impaired Loans, Recorded Investment	28,535,000	35,064,000
Total Impaired Loans, Unpaid Principal Balance	29,487,000	39,149,000
Impaired Loans with Specific Allowance, Average Recorded Investment	14,222,000	18,024,000
Impaired Loans with Specific Allowance, Interest Income Recognized	592,000	781,000
Impaired Loans with No Specific Allowance, Average Recorded Investment	17,342,000	28,941,000
Impaired Loans with No Related Allowance, Interest Income Recognized	648,000	1,148,000
Total Impaired Loans, Average Recorded Investment	31,564,000	46,965,000
Total Impaired Loans Interest Income Recognized	1,240,000	1,929,000
Impaired loans	28,535,000	35,064,000
Total loans	309,461,000	258,919,000
Residential Mortgage [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	295,589,000	240,325,000
Construction Acquisition and Development [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	0	0
Impaired Loans with Specific Allowance, Related Allowance	0	0
Impaired Loans with No Specific Allowance, Recorded Investment	917,000	2,808,000
Total Impaired Loans, Recorded Investment	917,000	2,808,000
Total Impaired Loans, Unpaid Principal Balance	917,000	3,453,000
Impaired Loans with Specific Allowance, Average Recorded Investment	0	952,000
Impaired Loans with Specific Allowance, Interest Income Recognized	0	44,000
Impaired Loans with No Specific Allowance, Average Recorded Investment	1,831,000	5,284,000
Impaired Loans with No Related Allowance, Interest Income Recognized	54,000	164,000
Total Impaired Loans, Average Recorded Investment	1,831,000	6,236,000
Total Impaired Loans Interest Income Recognized	54,000	208,000
Impaired loans	917,000	2,808,000
Total loans	84,325,000	75,539,000
Construction Acquisition and Development [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	82,778,000	72,104,000
Land [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	355,000	363,000
Impaired Loans with Specific Allowance, Related Allowance	53,000	67,000
Impaired Loans with No Specific Allowance, Recorded Investment	1,684,000	900,000
Total Impaired Loans, Recorded Investment	2,039,000	1,263,000
Total Impaired Loans, Unpaid Principal Balance	2,157,000	1,380,000
Impaired Loans with Specific Allowance, Average Recorded Investment	359,000	1,920,000
Impaired Loans with Specific Allowance, Interest Income Recognized	13,000	59,000
Impaired Loans with No Specific Allowance, Average Recorded Investment	1,774,000	1,538,000
Impaired Loans with No Related Allowance, Interest Income Recognized	89,000	79,000
Total Impaired Loans, Average Recorded Investment	2,133,000	3,458,000
Total Impaired Loans Interest Income Recognized	102,000	138,000
Impaired loans	2,039,000	1,263,000
Total loans	30,426,000	34,429,000
Land [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	30,285,000	33,804,000
Lines of Credit [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	0	0
Impaired Loans with Specific Allowance, Related Allowance	0	0
Impaired Loans with No Specific Allowance, Recorded Investment	454,000	304,000
Total Impaired Loans, Recorded Investment	454,000	304,000
Total Impaired Loans, Unpaid Principal Balance	545,000	395,000
Impaired Loans with Specific Allowance, Average Recorded Investment	599,000	0
Impaired Loans with Specific Allowance, Interest Income Recognized	15,000	0
Impaired Loans with No Specific Allowance, Average Recorded Investment	616,000	365,000
Impaired Loans with No Related Allowance, Interest Income Recognized	41,000	24,000
Total Impaired Loans, Average Recorded Investment	1,215,000	365,000
Total Impaired Loans Interest Income Recognized	56,000	24,000
Impaired loans	454,000	304,000
Total loans	19,251,000	21,598,000
Lines of Credit [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	16,112,000	19,152,000
Commercial Real Estate [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	2,529,000	2,092,000
Impaired Loans with Specific Allowance, Related Allowance	224,000	241,000
Impaired Loans with No Specific Allowance, Recorded Investment	3,780,000	2,580,000
Total Impaired Loans, Recorded Investment	6,309,000	4,672,000
Total Impaired Loans, Unpaid Principal Balance	6,533,000	4,685,000
Impaired Loans with Specific Allowance, Average Recorded Investment	2,556,000	5,698,000
Impaired Loans with Specific Allowance, Interest Income Recognized	120,000	272,000
Impaired Loans with No Specific Allowance, Average Recorded Investment	4,515,000	6,949,000
Impaired Loans with No Related Allowance, Interest Income Recognized	230,000	270,000
Total Impaired Loans, Average Recorded Investment	7,071,000	12,647,000
Total Impaired Loans Interest Income Recognized	350,000	542,000
Impaired loans	6,309,000	4,672,000
Total loans	198,539,000	220,160,000
Commercial Real Estate [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	181,686,000	205,063,000
Commercial Non-Real Estate [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	274,000	0
Impaired Loans with Specific Allowance, Related Allowance	15,000	0
Impaired Loans with No Specific Allowance, Recorded Investment	0	0
Total Impaired Loans, Recorded Investment	274,000	0
Total Impaired Loans, Unpaid Principal Balance	274,000	0
Impaired Loans with Specific Allowance, Average Recorded Investment	258,000	0
Impaired Loans with Specific Allowance, Interest Income Recognized	5,000	0
Impaired Loans with No Specific Allowance, Average Recorded Investment	406,000	0
Impaired Loans with No Related Allowance, Interest Income Recognized	23,000	0
Total Impaired Loans, Average Recorded Investment	664,000	0
Total Impaired Loans Interest Income Recognized	28,000	0
Impaired loans	274,000	0
Total loans	10,167,000	8,583,000
Commercial Non-Real Estate [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	9,275,000	8,583,000
Home Equity [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	1,472,000	491,000
Impaired Loans with Specific Allowance, Related Allowance	370,000	246,000
Impaired Loans with No Specific Allowance, Recorded Investment	2,079,000	1,286,000
Total Impaired Loans, Recorded Investment	3,551,000	1,777,000
Total Impaired Loans, Unpaid Principal Balance	4,274,000	2,239,000
Impaired Loans with Specific Allowance, Average Recorded Investment	1,460,000	491,000
Impaired Loans with Specific Allowance, Interest Income Recognized	0	22,000
Impaired Loans with No Specific Allowance, Average Recorded Investment	2,174,000	1,684,000
Impaired Loans with No Related Allowance, Interest Income Recognized	65,000	88,000
Total Impaired Loans, Average Recorded Investment	3,634,000	2,175,000
Total Impaired Loans Interest Income Recognized	65,000	110,000
Impaired loans	3,551,000	1,777,000
Total loans	28,750,000	30,339,000
Home Equity [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	25,769,000	28,447,000
Consumer [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	12,000	0
Impaired Loans with Specific Allowance, Related Allowance	2,000	0
Impaired Loans with No Specific Allowance, Recorded Investment	0	0
Total Impaired Loans, Recorded Investment	12,000	0
Total Impaired Loans, Unpaid Principal Balance	12,000	0
Impaired Loans with Specific Allowance, Average Recorded Investment	13,000	0
Impaired Loans with Specific Allowance, Interest Income Recognized	0	0
Impaired Loans with No Specific Allowance, Average Recorded Investment	0	1,077,000
Impaired Loans with No Related Allowance, Interest Income Recognized	0	43,000
Total Impaired Loans, Average Recorded Investment	13,000	1,077,000
Total Impaired Loans Interest Income Recognized	0	43,000
Impaired loans	12,000	0
Total loans	1,040,000	1,185,000
Consumer [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	985,000	299,000
Residential Real Estate [Member]
Impaired loans [Abstract]
Total Impaired Loans, Recorded Investment	28,535,000
Impaired loans	28,535,000
Unfunded [Member]
Impaired loans [Abstract]
Total loans	36,162,000	34,069,000
Unfunded [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	36,162,000	34,069,000
Consumer Residential Real Estate [Member]
Impaired loans [Abstract]
Total Impaired Loans, Recorded Investment	23,626,000
Impaired loans	23,626,000
Builders Residential Real Estate [Member]
Impaired loans [Abstract]
Total Impaired Loans, Recorded Investment	4,909,000
Impaired loans	$ 4,909,000

Amount of loans that are not in non accrual status.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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

-Publisher FASB

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-Topic 310

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-Section 50

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Amount of allowance for credit losses related to recorded investment.

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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Amount of interest income, recognized on accrual basis, on financing receivables that are recognized as impaired, for which there is no related allowance for credit losses.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Amount of average investment of impaired financing receivables for which there is a related allowance for credit losses.

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Amount of interest income, recognized on accrual basis, on financing receivables, for which there is a related allowance for credit losses and are recognized as impaired.

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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