Note 3 - Loans Receivable - Schedule of Financing Receivable Restructuring (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Modified, Amortized cost	$ 959	$ 156	$ 1,465
Modified, Number	5	1	9
Modified, Number	5	1	9
Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost	$ 953	$ 156	$ 1,250
Extended Maturity and Interest Rate Reduction [Member]
Modified, Amortized cost	6	0	215
Commercial Portfolio Segment [Member] \| Agricultural Loan [Member]
Modified, Amortized cost	$ 156	$ 156	$ 409
Modified, Number	2	1	4
Modified, Number	2	1	4
Commercial Portfolio Segment [Member] \| Agricultural Loan [Member] \| Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost	$ 150	$ 156	$ 403
Total Financing Receivables, Percentage	0.10%	0.11%	0.26%
Commercial Portfolio Segment [Member] \| Agricultural Loan [Member] \| Extended Maturity and Interest Rate Reduction [Member]
Modified, Amortized cost	$ 6	$ 0	$ 6
Total Financing Receivables, Percentage	0.00%	0.00%	0.00%
Commercial Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Modified, Amortized cost			$ 209
Modified, Number			1
Modified, Number			1
Commercial Portfolio Segment [Member] \| Commercial Real Estate Loan [Member] \| Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost			$ 0
Total Financing Receivables, Percentage			0.00%
Commercial Portfolio Segment [Member] \| Commercial Real Estate Loan [Member] \| Extended Maturity and Interest Rate Reduction [Member]
Modified, Amortized cost			$ 209
Total Financing Receivables, Percentage			0.03%
Residential Portfolio Segment [Member] \| One-to-Four Family Loans [Member]
Modified, Amortized cost	$ 625		$ 625
Modified, Number	1		1
Modified, Number	1		1
Residential Portfolio Segment [Member] \| One-to-Four Family Loans [Member] \| Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost	$ 625		$ 625
Total Financing Receivables, Percentage	0.42%		0.42%
Residential Portfolio Segment [Member] \| One-to-Four Family Loans [Member] \| Extended Maturity and Interest Rate Reduction [Member]
Modified, Amortized cost	$ 0		$ 0
Total Financing Receivables, Percentage	0.00%		0.00%
Commercial Real Estate Portfolio Segment [Member] \| Farmland Loan [Member]
Modified, Amortized cost	$ 108		$ 108
Modified, Number	1		1
Modified, Number	1		1
Commercial Real Estate Portfolio Segment [Member] \| Farmland Loan [Member] \| Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost	$ 108		$ 108
Total Financing Receivables, Percentage	0.07%		0.07%
Commercial Real Estate Portfolio Segment [Member] \| Farmland Loan [Member] \| Extended Maturity and Interest Rate Reduction [Member]
Modified, Amortized cost	$ 0		$ 0
Total Financing Receivables, Percentage	0.00%		0.00%
Home Equity Portfolio Segment [Member]
Modified, Amortized cost	$ 70		$ 114
Modified, Number	1		2
Modified, Number	1		2
Home Equity Portfolio Segment [Member] \| Payment Deferral and Extended Maturity [Member]
Modified, Amortized cost	$ 70		$ 114
Total Financing Receivables, Percentage	0.07%		0.11%
Home Equity Portfolio Segment [Member] \| Extended Maturity and Interest Rate Reduction [Member]
Modified, Amortized cost	$ 0		$ 0
Total Financing Receivables, Percentage	0.00%		0.00%

The number of financing receivable, excluding accrued interest, of modified during period for debtor experiencing financial difficulty.

No definition available.

+ Details

Name:	ebmt_FinancingReceivableExcludingAccruedInterestModifiedInPeriodNumber
Namespace Prefix:	ebmt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

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Period Type:	duration

- Definition

Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

+ References

+ Details

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- Details

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- Details

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