The amount of reclassification of tax effect from accumulated other comprehensive income.

No definition available.

Name:	lmst_ReclassificationOfTaxEffectsFromAOCI
Namespace Prefix:	lmst_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Minimum amount of regulatory capital required for Federal Home Loan Bank (FHLBank), set by the Federal Housing Finance Agency (FHFA).

+ References

No definition available.

+ Details

Name:	us-gaap_FederalHomeLoanBankRegulatoryCapitalRequired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

+ Details

Name:	us-gaap_OperatingLeaseLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

+ Details

Name:	us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

Name:	us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedOtherComprehensiveIncomeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_RetainedEarningsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201602Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=lmst_AccountingStandardsUpdate201802Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_FurnitureAndFixturesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=lmst_LimestoneBankMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2018	Jan. 01, 2019	Dec. 31, 2017
Federal Home Loan Bank, Regulatory Capital, Required	$ 7,400,000		$ 11,000,000
Reclassification of Tax Effects From AOCI
AOCI Attributable to Parent [Member]
Reclassification of Tax Effects From AOCI	(113,000)
Retained Earnings [Member]
Reclassification of Tax Effects From AOCI	113,000
Accounting Standards Update 2016-02 [Member] \| Subsequent Event [Member]
Operating Lease, Liability, Total		$ 700,000
Operating Lease, Right-of-Use Asset		$ 700,000
Accounting Standards Update 2018-02 [Member] \| AOCI Attributable to Parent [Member]
Reclassification of Tax Effects From AOCI	(113,000)
Accounting Standards Update 2018-02 [Member] \| Retained Earnings [Member]
Reclassification of Tax Effects From AOCI	$ 113,000
Minimum [Member] \| Building [Member]
Property, Plant and Equipment, Useful Life	5 years
Minimum [Member] \| Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life	2 years
Maximum [Member] \| Building [Member]
Property, Plant and Equipment, Useful Life	40 years
Maximum [Member] \| Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life	10 years
Limestone Bank [Member]
Noncontrolling Interest, Ownership Percentage by Parent	100.00%