Guarantee percentage.

No definition available.

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Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

No definition available.

+ Details

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Namespace Prefix:	mgyr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of expected lives.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Troubled Debt Restructurings Loans.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- 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

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28555-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The gross interest income that would have been recorded in the period on troubled debt restructurings, if the loans had been current in accordance with their original terms and had been outstanding throughout the period or since origination, if held for part of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from a borrowing supported by a written promise to pay an obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The portion of the carrying amount of short-term borrowings outstanding as of the balance sheet date which accrues interest at a set, unchanging rate.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

- Details

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Balance Type:
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- Details

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Balance Type:
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- Details

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LOANS RECEIVABLE, NET AND RELATED ALLOWANCE FOR LOAN LOSSES (Narrative) (Details) $ in Thousands	3 Months Ended		6 Months Ended	9 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) Loans	Jun. 30, 2020 USD ($) N	Jun. 30, 2019 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average Recorded Investment	$ 12,058	$ 8,930		$ 10,836	$ 8,863
Interest income				$ 104	179
Troubled Debt Restructurings Loans		$ 365			$ 365
Number of loans \| N				1
Paycheck Protection Program Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest rate of loan	1.00%		1.00%	1.00%
Number of loans \| Loans			341
Loan received			$ 55,900
Loan origination fees	$ 2,000		$ 2,000	$ 2,000
Paycheck Protection Program Loan [Member] \| Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Expected life of loans			2 years
Paycheck Protection Program Loan [Member] \| Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Expected life of loans			5 years
Paycheck Protection Program Loan [Member] \| SBA [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Guarantee percentage			100.00%