INVESTMENT SECURITIES - Securities with unrealized losses (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Less than 12 Months
Fair Value	$ 9,008	$ 58,574
Unrecognized Losses	(555)	(4,543)
12 Months or Longer
Fair Value	59,921	15,339
Unrecognized Losses	(7,445)	(1,808)
Total
Fair Value	68,929	73,913
Unrecognized Losses	(8,000)	(6,351)
U.S. Treasury debt
Less than 12 Months
Fair Value	0	0
Unrecognized Losses	0	0
12 Months or Longer
Fair Value	237	234
Unrecognized Losses	(10)	(9)
Total
Fair Value	237	234
Unrecognized Losses	(10)	(9)
Corporate bonds
Less than 12 Months
Fair Value	0	20,911
Unrecognized Losses	0	(2,436)
12 Months or Longer
Fair Value	20,251	455
Unrecognized Losses	(3,507)	(17)
Total
Fair Value	20,251	21,366
Unrecognized Losses	(3,507)	(2,453)
GNMA mortgage-backed securities – residential
Less than 12 Months
Fair Value	6,267	22,371
Unrecognized Losses	(393)	(1,051)
12 Months or Longer
Fair Value	27,377	14,255
Unrecognized Losses	(2,885)	(1,749)
Total
Fair Value	33,644	36,626
Unrecognized Losses	(3,278)	(2,800)
FNMA mortgage-backed securities – residential
Less than 12 Months
Fair Value	0	6,202
Unrecognized Losses	0	(506)
12 Months or Longer
Fair Value	5,825	0
Unrecognized Losses	(545)	0
Total
Fair Value	5,825	6,202
Unrecognized Losses	(545)	(506)
Government CMO and MBS - commercial
Less than 12 Months
Fair Value	52	5,591
Unrecognized Losses		(403)
12 Months or Longer
Fair Value	5,241	0
Unrecognized Losses	(412)	0
Total
Fair Value	5,293	5,591
Unrecognized Losses	(412)	(403)
Corporate CMO and MBS
Less than 12 Months
Fair Value	2,689	3,499
Unrecognized Losses	(162)	(147)
12 Months or Longer
Fair Value	990	395
Unrecognized Losses	(86)	(33)
Total
Fair Value	3,679	3,894
Unrecognized Losses	$ (248)	$ (180)

Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months Or Longer

No definition available.

Name:	myfw_DebtSecuritiesHeldToMaturityContinuousUnrealizedLossPosition12MonthsOrLongerAbstract
Namespace Prefix:	myfw_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months

+ References

No definition available.

+ Details

Name:	myfw_DebtSecuritiesHeldToMaturityContinuousUnrealizedLossPositionLessThan12MonthsAbstract
Namespace Prefix:	myfw_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-5A

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-5

+ Details

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

- Definition

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-7

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-6

+ Details

Name:	us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
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), in unrealized loss position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-6

+ Details

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

- Definition

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for less than 12 months.

+ References

+ Details

Name:	us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
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), in continuous unrealized loss position for less than 12 months.

+ References

+ Details

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

- References

No definition available.

+ Details

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

- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for 12 months or longer.

+ References

+ Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
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: