LOANS, Impaired Loans by Class of Loans (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Loans on Nonaccrual Status [Abstract]
Loans on Nonaccrual Status	$ 10,701,000	$ 5,099,000
With no related allowance recorded [Abstract]
Recorded Investment	3,034,000	3,173,000
Unpaid Principal Balance	3,117,000	4,083,000
Related Allowance	0	0
Average Recorded Investment	3,103,000	4,363,000
Interest Income Recognized	32,000	26,000
With an allowance recorded [Abstract]
Recorded Investment	7,513,000	1,552,000
Unpaid Principal Balance	7,661,000	1,572,000
Related Allowance	2,164,000	405,000
Average Recorded Investment	4,533,000	1,720,000
Interest Income Recognized	262,000	21,000
Totals [Abstract]
Recorded Investment	10,547,000	4,725,000
Unpaid Principal Balance	10,778,000	5,655,000
Related Allowance	2,164,000	405,000
Average Recorded Investment	7,636,000	6,083,000
Interest Income Recognized	294,000	47,000
Interest lost on nonaccrual loans	594,000	518,000	582,000
Interest received on nonaccrual loans	105,000msl_InterestReceivedOnNonaccrualLoans	312,000msl_InterestReceivedOnNonaccrualLoans	70,000msl_InterestReceivedOnNonaccrualLoans
Commercial, Financial and Agricultural [Member]
Loans on Nonaccrual Status [Abstract]
Loans on Nonaccrual Status	2,642,000	1,272,000
With no related allowance recorded [Abstract]
Recorded Investment	438,000	671,000
Unpaid Principal Balance	521,000	1,107,000
Related Allowance	0	0
Average Recorded Investment	554,000	617,000
Interest Income Recognized	0	3,000
With an allowance recorded [Abstract]
Recorded Investment	2,218,000	570,000
Unpaid Principal Balance	2,333,000	570,000
Related Allowance	1,010,000	168,000
Average Recorded Investment	1,394,000	821,000
Interest Income Recognized	35,000	3,000
Totals [Abstract]
Related Allowance	1,010,000	168,000
Commercial Real Estate Construction [Member]
Loans on Nonaccrual Status [Abstract]
Loans on Nonaccrual Status	54,000	100,000
With no related allowance recorded [Abstract]
Recorded Investment	54,000	61,000
Unpaid Principal Balance	54,000	61,000
Related Allowance	0	0
Average Recorded Investment	58,000	416,000
Interest Income Recognized	0	0
With an allowance recorded [Abstract]
Recorded Investment	0	39,000
Unpaid Principal Balance	0	39,000
Related Allowance	0	3,000
Average Recorded Investment	19,000	102,000
Interest Income Recognized	0	1,000
Totals [Abstract]
Related Allowance	0	3,000
Commercial Real Estate - Other [Member]
Loans on Nonaccrual Status [Abstract]
Loans on Nonaccrual Status	6,429,000	2,290,000
With no related allowance recorded [Abstract]
Recorded Investment	1,921,000	1,850,000
Unpaid Principal Balance	1,921,000	2,324,000
Related Allowance	0	0
Average Recorded Investment	1,885,000	2,190,000
Interest Income Recognized	17,000	8,000
With an allowance recorded [Abstract]
Recorded Investment	4,467,000	363,000
Unpaid Principal Balance	4,467,000	363,000
Related Allowance	907,000	54,000
Average Recorded Investment	2,416,000	372,000
Interest Income Recognized	220,000	11,000
Totals [Abstract]
Related Allowance	907,000	54,000
Consumer - Other [Member]
Loans on Nonaccrual Status [Abstract]
Loans on Nonaccrual Status	382,000	284,000
With no related allowance recorded [Abstract]
Recorded Investment	78,000	66,000
Unpaid Principal Balance	78,000	66,000
Related Allowance	0	0
Average Recorded Investment	72,000	90,000
Interest Income Recognized	0	1,000
With an allowance recorded [Abstract]
Recorded Investment	299,000	205,000
Unpaid Principal Balance	313,000	205,000
Related Allowance	179,000	120,000
Average Recorded Investment	252,000	211,000
Interest Income Recognized	4,000	2,000
Totals [Abstract]
Related Allowance	179,000	120,000
Residential - Prime [Member]
Loans on Nonaccrual Status [Abstract]
Loans on Nonaccrual Status	1,194,000	1,153,000
With no related allowance recorded [Abstract]
Recorded Investment	543,000	525,000
Unpaid Principal Balance	543,000	525,000
Related Allowance	0	0
Average Recorded Investment	534,000	1,050,000
Interest Income Recognized	15,000	14,000
With an allowance recorded [Abstract]
Recorded Investment	529,000	375,000
Unpaid Principal Balance	548,000	395,000
Related Allowance	68,000	60,000
Average Recorded Investment	452,000	214,000
Interest Income Recognized	3,000	4,000
Totals [Abstract]
Related Allowance	68,000	60,000
Lease Financing Receivable [Member]
Loans on Nonaccrual Status [Abstract]
Loans on Nonaccrual Status	0	0
Other Loans [Member]
Loans on Nonaccrual Status [Abstract]
Loans on Nonaccrual Status	0	0
Commercial Total [Member]
With an allowance recorded [Abstract]
Related Allowance	1,917,000	225,000
Totals [Abstract]
Recorded Investment	9,098,000	3,554,000
Unpaid Principal Balance	9,296,000	4,464,000
Related Allowance	1,917,000	225,000
Average Recorded Investment	6,326,000	4,518,000
Interest Income Recognized	272,000	26,000
Consumer Total [Member]
With an allowance recorded [Abstract]
Related Allowance	179,000	120,000
Totals [Abstract]
Recorded Investment	377,000	271,000
Unpaid Principal Balance	391,000	271,000
Related Allowance	179,000	120,000
Average Recorded Investment	324,000	301,000
Interest Income Recognized	4,000	3,000
Residential Total [Member]
With an allowance recorded [Abstract]
Related Allowance	68,000	60,000
Totals [Abstract]
Recorded Investment	1,072,000	900,000
Unpaid Principal Balance	1,091,000	920,000
Related Allowance	68,000	60,000
Average Recorded Investment	986,000	1,264,000
Interest Income Recognized	18,000	18,000
Consumer - Credit Card [Member]
Loans on Nonaccrual Status [Abstract]
Loans on Nonaccrual Status	0	0
Residential Construction [Member]
Loans on Nonaccrual Status [Abstract]
Loans on Nonaccrual Status	$ 0	$ 0

Amount of allowance for credit losses related to recorded investment with no related allowance recorded.

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This line item represents the interest received on nonaccrual loans.

+ References

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

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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.

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

-Publisher FASB

-Name Accounting Standards Codification

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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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-Publisher FASB

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

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Amount of interest income, recognized on cash basis, on financing receivables, for which there is no 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 no related allowance for credit losses.

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Amount of unpaid principal balance of 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 on financing receivables, for which there is a related allowance for credit losses, recognized on a cash-basis method of accounting that the financing receivables were 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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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

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

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