Securities (Fair Value to Amortized Cost Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, available for sale	$ 128,922	$ 122,524
Gross unrealized gains, available for sale	2,538	209
Gross unrealized losses, available for sale	172	2,757
Estimated fair value, available for sale	131,288	119,976
Amortized cost, Held-to-maturity Securities	88,654	96,271
Gross unrealized gains, held to maturity	1,562	146
Gross unrealized losses, held to maturity	181	2,672
Debt Securities, Held-to-maturity, Fair Value	90,035	93,745
Equity securities carried at fair value through income, Estimated Fair Value	4,665	4,428
Non-marketable equity securities held in other financial institutions	209	209
Non-marketable equity securities in other financial institutions, Estimated Fair Value	209	209
Residential Mortgage Backed Securities Issued By US Government Sponsored Enterprises [Member]
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, available for sale	11,686	7,641
Gross unrealized gains, available for sale	115	1
Gross unrealized losses, available for sale	9	281
Estimated fair value, available for sale	11,792	7,361
Amortized cost, Held-to-maturity Securities	27,707	25,948
Gross unrealized gains, held to maturity	901	75
Gross unrealized losses, held to maturity	16	756
Debt Securities, Held-to-maturity, Fair Value	28,592	25,267
Residential Collateralized Mortgage Obligations, Issued By US Government Sponsored Enterprises [Member]
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, available for sale	106,038	102,411
Gross unrealized gains, available for sale	2,289	199
Gross unrealized losses, available for sale	133	1,870
Estimated fair value, available for sale	108,194	100,740
Amortized cost, Held-to-maturity Securities	47,195	52,375
Gross unrealized gains, held to maturity	457	64
Gross unrealized losses, held to maturity	139	1,360
Debt Securities, Held-to-maturity, Fair Value	47,513	51,079
US Agency [Member]
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, available for sale	11,198	12,472
Gross unrealized gains, available for sale	134	9
Gross unrealized losses, available for sale	30	606
Estimated fair value, available for sale	11,302	11,875
Amortized cost, Held-to-maturity Securities	9,597	10,508
Gross unrealized gains, held to maturity	197	7
Gross unrealized losses, held to maturity	13	404
Debt Securities, Held-to-maturity, Fair Value	9,781	10,111
Residential Collateralized Mortgage Obligations, Issued By Private Enterprises [Member]
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, Held-to-maturity Securities	408	482
Gross unrealized gains, held to maturity	4
Gross unrealized losses, held to maturity	13	41
Debt Securities, Held-to-maturity, Fair Value	399	441
Us Government Agencies Callable Agency Bonds [Member]
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, Held-to-maturity Securities	2,003	5,009
Gross unrealized gains, held to maturity	3
Gross unrealized losses, held to maturity		110
Debt Securities, Held-to-maturity, Fair Value	2,006	4,899
Certificates of Deposit Fixed [Member]
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, Held-to-maturity Securities	250	950
Debt Securities, Held-to-maturity, Fair Value	250	950
US Government Obligations [Member]
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, Held-to-maturity Securities	1,494	999
Gross unrealized losses, held to maturity		1
Debt Securities, Held-to-maturity, Fair Value	1,494	998
CRA Investment Fund [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity securities carried at fair value through income	4,665	4,428
Equity securities carried at fair value through income, Estimated Fair Value	4,665	4,428
Other Equity Securities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Non-marketable equity securities held in other financial institutions	209	209
Non-marketable equity securities in other financial institutions, Estimated Fair Value	$ 209	$ 209

Equity Securities Carried At Fair Value Through Income

No definition available.

Name:	tcfc_EquitySecuritiesCarriedAtFairValueThroughIncome
Namespace Prefix:	tcfc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Equity Securities Carried At Fair Value Through Income, Estimated Fair Value

+ References

No definition available.

+ Details

Name:	tcfc_EquitySecuritiesCarriedAtFairValueThroughIncomeEstimatedFairValue
Namespace Prefix:	tcfc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Non-Marketable Equity Securities Held In Other Financial Institutions

+ References

No definition available.

+ Details

Name:	tcfc_NonMarketableEquitySecuritiesHeldInOtherFinancialInstitutions
Namespace Prefix:	tcfc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Non-Marketable Equity Securities Held In Other Financial Institutions, Estimated Fair Value.

+ References

No definition available.

+ Details

Name:	tcfc_NonMarketableEquitySecuritiesHeldInOtherFinancialInstitutionsEstimatedFairValue
Namespace Prefix:	tcfc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

+ Details

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

- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

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

- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

+ Details

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

- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

+ Details

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

- Definition

Amount of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

+ Details

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

- Definition

Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

+ Details

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

- Definition

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

+ Details

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

- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FinancialInstrumentAxis=tcfc_ResidentialMortgageBackedSecuritiesIssuedByUsGovernmentSponsoredEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=tcfc_ResidentialCollateralizedMortgageObligationsIssuedByUsGovernmentSponsoredEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=tcfc_AssetBackedSecuritiesIssuedByUsAgenciesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=tcfc_UsGovernmentAgenciesCallableAgencyBondsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_FixedIncomeSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=tcfc_CraInvestmentFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=tcfc_OtherEquitySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: