Delinquent loans.

No definition available.

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Period Type:	instant

- Definition

Deliquency period of loan.

+ References

No definition available.

+ Details

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- Definition

The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy. Specific to escrow deposits held for loans serviced on behalf of others.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The principal balance of interest-only mortgage loans receivable on the company's books as of the balance sheet date.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The value of capitalized mortgage servicing rights.

+ References

No definition available.

+ Details

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

- 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

TDR loans.

+ References

No definition available.

+ Details

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Namespace Prefix:	mgyr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

TDR loans defaulted.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of contractually required payments receivable at acquisition of acquired loans accounted for as available-for-sale debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due after one year (or one business cycle).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 850
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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

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Period Type:	duration

- 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
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Period Type:	duration

- Definition

The increase (decrease) during the reporting period in receivables to be collected from other entities that could exert significant influence over the reporting entity.

+ References

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-SubTopic 10
-Section 45
-Paragraph 28
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Balance Type:	credit
Period Type:	duration

- Definition

The increase (decrease) during the reporting period in the amount owed to the reporting entity in the form of loans and obligations (generally evidenced by promissory notes) made to the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management, an entity and its principal owners, management, or member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

+ References

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- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

+ Details

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Balance Type:	credit
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- Definition

Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

+ References

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Balance Type:	debit
Period Type:	instant

- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

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+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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- Details

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- Details

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LOANS RECEIVABLE, NET (Narrative) (Details) $ in Thousands	1 Months Ended	12 Months Ended
LOANS RECEIVABLE, NET (Narrative) (Details) $ in Thousands	Nov. 30, 2020 USD ($) N	Sep. 30, 2020 USD ($) N	Sep. 30, 2019 USD ($) N
Financing Receivable, Past Due [Line Items]
Loans receivable from directors, executives, affiliates		$ 2,500	$ 2,900
Principal Additions - loans receivable-related parties		400	502
Principal Repayments - loans receivable-related parties		775	233
Value of loans serviced on behalf of others		42,700	42,300
Mortgage Servicing Rights		12	26
Escrow balance held for loans serviced on behalf of others		61	78
Average Recorded Investment		11,700	9,200
Interest Income not recognized on non-accrual loans		508	530
Interest-only mortgage loans
Loans pledged as collateral against Federal Home Loan Bank of New York borrowings		184,100	176,900
Troubled Debt Restructurings Loans		2,900
Troubled Debt Restructurings Loans defaulted
Delinquent loans		11,400
Interest income		$ 142	$ 165
Number of Loans \| N		1	1
Subsequent Event [Member]
Financing Receivable, Past Due [Line Items]
Number of Loans \| N	270
Loans resumed for contractual scheduled payments	$ 141,400
Subsequent Event [Member] \| Payment Deferral [Member]
Financing Receivable, Past Due [Line Items]
Number of Loans \| N	11
Loans resumed for contractual scheduled payments	$ 7,800
Subsequent Event [Member] \| Loans Delinquent [Member]
Financing Receivable, Past Due [Line Items]
Number of Loans \| N	2
Loans resumed for contractual scheduled payments	$ 1,500
Subsequent Event [Member] \| Loans Delinquent One [Member]
Financing Receivable, Past Due [Line Items]
Loans resumed for contractual scheduled payments	$ 1,400
Deliquency period of loan	90 days
Subsequent Event [Member] \| Loans Delinquent Two [Member]
Financing Receivable, Past Due [Line Items]
Loans resumed for contractual scheduled payments	$ 113
Deliquency period of loan	30 days