Loans Receivable, Non-Performing Assets and Impaired Loans (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	$ 16,773,000		$ 18,736,000
Impaired Loans with Specific Allowance, Related Allowance	2,254,000		2,777,000
Impaired Loans with No Specific Allowance, Recorded Investment	23,317,000		23,355,000
Total Impaired Loans, Recorded Investment	40,090,000		42,091,000
Total Impaired Loans, Unpaid Principal Balance	40,264,000		44,199,000
Impaired Loans with Specific Allowance, Average Recorded Investment	17,154,000	17,521,000
Impaired Loans with Specific Allowance, Interest Income Recognized	172,000	199,000
Impaired Loans with No Specific Allowance, Average Recorded Investment	23,660,000	30,980,000
Impaired Loans with No Specific Allowance, Interest Income Recognized	283,000	368,000
Total Impaired Loans, Average Recorded Investment	40,814,000	48,501,000
Total Impaired Loans Interest Income Recognized	455,000	567,000
Interest income on cash basis recognized on impaired loans	455,000	567,000
Loans in nonaccrual status included in impaired loans	26,773,000svbi_LoansThatAreNotInNonAccrualStatus
Impaired loans	40,090,000		42,091,000
Total loans	661,648,000		681,959,000
Pass [Member]
Impaired loans [Abstract]
Total loans	618,740,000		642,479,000
Residential Mortgage [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	13,626,000		14,094,000
Impaired Loans with Specific Allowance, Related Allowance	1,969,000		2,113,000
Impaired Loans with No Specific Allowance, Recorded Investment	15,254,000		14,441,000
Total Impaired Loans, Recorded Investment	28,880,000		28,535,000
Total Impaired Loans, Unpaid Principal Balance	29,765,000		29,487,000
Impaired Loans with Specific Allowance, Average Recorded Investment	13,648,000	15,076,000
Impaired Loans with Specific Allowance, Interest Income Recognized	136,000	167,000
Impaired Loans with No Specific Allowance, Average Recorded Investment	15,343,000	18,702,000
Impaired Loans with No Specific Allowance, Interest Income Recognized	148,000	225,000
Total Impaired Loans, Average Recorded Investment	28,991,000	33,778,000
Total Impaired Loans Interest Income Recognized	284,000	392,000
Impaired loans	28,880,000		28,535,000
Total loans	309,904,000		309,461,000
Residential Mortgage [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	291,830,000		295,589,000
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	919,000		917,000
Total Impaired Loans, Recorded Investment	919,000		917,000
Total Impaired Loans, Unpaid Principal Balance	919,000		917,000
Impaired Loans with Specific Allowance, Average Recorded Investment	0	0
Impaired Loans with Specific Allowance, Interest Income Recognized	0	0
Impaired Loans with No Specific Allowance, Average Recorded Investment	1,157,000	2,735,000
Impaired Loans with No Specific Allowance, Interest Income Recognized	9,000	19,000
Total Impaired Loans, Average Recorded Investment	1,157,000	2,735,000
Total Impaired Loans Interest Income Recognized	9,000	19,000
Impaired loans	919,000		917,000
Total loans	81,418,000		84,325,000
Construction Acquisition and Development [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	79,780,000		82,778,000
Land [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	353,000		355,000
Impaired Loans with Specific Allowance, Related Allowance	49,000		53,000
Impaired Loans with No Specific Allowance, Recorded Investment	1,595,000		1,684,000
Total Impaired Loans, Recorded Investment	1,948,000		2,039,000
Total Impaired Loans, Unpaid Principal Balance	2,065,000		2,157,000
Impaired Loans with Specific Allowance, Average Recorded Investment	354,000	362,000
Impaired Loans with Specific Allowance, Interest Income Recognized	3,000	3,000
Impaired Loans with No Specific Allowance, Average Recorded Investment	1,676,000	1,187,000
Impaired Loans with No Specific Allowance, Interest Income Recognized	22,000	14,000
Total Impaired Loans, Average Recorded Investment	2,030,000	1,549,000
Total Impaired Loans Interest Income Recognized	25,000	17,000
Impaired loans	1,948,000		2,039,000
Total loans	30,043,000		30,426,000
Land [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	29,903,000		30,285,000
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	453,000		454,000
Total Impaired Loans, Recorded Investment	453,000		454,000
Total Impaired Loans, Unpaid Principal Balance	545,000		545,000
Impaired Loans with Specific Allowance, Average Recorded Investment	0	0
Impaired Loans with Specific Allowance, Interest Income Recognized	0	0
Impaired Loans with No Specific Allowance, Average Recorded Investment	454,000	1,937,000
Impaired Loans with No Specific Allowance, Interest Income Recognized	13,000	20,000
Total Impaired Loans, Average Recorded Investment	454,000	1,937,000
Total Impaired Loans Interest Income Recognized	13,000	20,000
Impaired loans	453,000		454,000
Total loans	17,651,000		19,251,000
Lines of Credit [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	14,486,000		16,112,000
Commercial Real Estate [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	2,513,000		2,529,000
Impaired Loans with Specific Allowance, Related Allowance	220,000		224,000
Impaired Loans with No Specific Allowance, Recorded Investment	1,949,000		3,780,000
Total Impaired Loans, Recorded Investment	4,462,000		6,309,000
Total Impaired Loans, Unpaid Principal Balance	4,580,000		6,533,000
Impaired Loans with Specific Allowance, Average Recorded Investment	2,518,000	2,083,000
Impaired Loans with Specific Allowance, Interest Income Recognized	31,000	29,000
Impaired Loans with No Specific Allowance, Average Recorded Investment	1,953,000	4,157,000
Impaired Loans with No Specific Allowance, Interest Income Recognized	40,000	68,000
Total Impaired Loans, Average Recorded Investment	4,471,000	6,240,000
Total Impaired Loans Interest Income Recognized	71,000	97,000
Impaired loans	4,462,000		6,309,000
Total loans	185,367,000		198,539,000
Commercial Real Estate [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	168,981,000		181,686,000
Commercial Non-Real Estate [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	269,000		274,000
Impaired Loans with Specific Allowance, Related Allowance	14,000		15,000
Impaired Loans with No Specific Allowance, Recorded Investment	0		0
Total Impaired Loans, Recorded Investment	269,000		274,000
Total Impaired Loans, Unpaid Principal Balance	269,000		274,000
Impaired Loans with Specific Allowance, Average Recorded Investment	270,000	0
Impaired Loans with Specific Allowance, Interest Income Recognized	2,000	0
Impaired Loans with No Specific Allowance, Average Recorded Investment	0	530,000
Impaired Loans with No Specific Allowance, Interest Income Recognized	13,000	7,000
Total Impaired Loans, Average Recorded Investment	270,000	530,000
Total Impaired Loans Interest Income Recognized	15,000	7,000
Impaired loans	269,000		274,000
Total loans	10,042,000		10,167,000
Commercial Non-Real Estate [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	9,421,000		9,275,000
Home Equity [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	0		1,472,000
Impaired Loans with Specific Allowance, Related Allowance	0		370,000
Impaired Loans with No Specific Allowance, Recorded Investment	3,147,000		2,079,000
Total Impaired Loans, Recorded Investment	3,147,000		3,551,000
Total Impaired Loans, Unpaid Principal Balance	4,109,000		4,274,000
Impaired Loans with Specific Allowance, Average Recorded Investment	352,000	0
Impaired Loans with Specific Allowance, Interest Income Recognized	0	0
Impaired Loans with No Specific Allowance, Average Recorded Investment	3,077,000	1,732,000
Impaired Loans with No Specific Allowance, Interest Income Recognized	38,000	15,000
Total Impaired Loans, Average Recorded Investment	3,429,000	1,732,000
Total Impaired Loans Interest Income Recognized	38,000	15,000
Impaired loans	3,147,000		3,551,000
Total loans	26,233,000		28,750,000
Home Equity [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	23,404,000		25,769,000
Consumer [Member]
Impaired loans [Abstract]
Impaired Loans with Specific Allowance, Recorded Investment	12,000		12,000
Impaired Loans with Specific Allowance, Related Allowance	2,000		2,000
Impaired Loans with No Specific Allowance, Recorded Investment	0		0
Total Impaired Loans, Recorded Investment	12,000		12,000
Total Impaired Loans, Unpaid Principal Balance	12,000		12,000
Impaired Loans with Specific Allowance, Average Recorded Investment	12,000	0
Impaired Loans with Specific Allowance, Interest Income Recognized	0	0
Impaired Loans with No Specific Allowance, Average Recorded Investment	0	0
Impaired Loans with No Specific Allowance, Interest Income Recognized	0	0
Total Impaired Loans, Average Recorded Investment	12,000	0
Total Impaired Loans Interest Income Recognized	0	0
Impaired loans	12,000		12,000
Total loans	990,000		1,040,000
Consumer [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	935,000		985,000
Residential Real Estate [Member]
Impaired loans [Abstract]
Total Impaired Loans, Recorded Investment	28,880,000
Impaired loans	28,880,000
Consumer Residential Real Estate [Member]
Impaired loans [Abstract]
Total Impaired Loans, Recorded Investment	24,040,000
Impaired loans	24,040,000
Builders Residential Real Estate [Member]
Impaired loans [Abstract]
Total Impaired Loans, Recorded Investment	4,840,000
Impaired loans	4,840,000
Unfunded [Member] \| Pass [Member]
Impaired loans [Abstract]
Total loans	$ 31,429,000		$ 36,162,000

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

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-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 interest income recognized on a cash-basis method of accounting 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

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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 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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