Name:	mtg_AnniversarypaymentreleaseofthestartoftheinterestdeferraltotheAlternativePaymentMechanisminlieuofthefinalmaturityofthedebentures
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The price per share of the conversion feature embedded in the debt instrument.

No definition available.

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The number of shares that can be issued in exchange for the original debt if converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

No definition available.

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Debt Instrument, Convertible, Number Of Equity Instruments Reserved For Conversion

No definition available.

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Debt Instrument, Ownership Percentage Threshold, Declaration Of Due And Payable

No definition available.

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Federal Home Loan Bank Advances, Collateral, Market Value Of Principal, Percent

No definition available.

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The maximum number of shares of common stock, including shares underlying qualifying warrants, that the entity may be required to issue pursuant to the Alternative Payment Mechanism under the note agreement(s).

No definition available.

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The maximum number of trading days within a specified time period that the closing sale price of the entity's common stock exceeds the prevailing conversion price of the debentures by a specified percentage.

No definition available.

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The maximum ratio of total net proceeds of all issuances of qualifying securities to the aggregate principal amount of the debentures. Pursuant to the Alternative Payment Mechanism under the note agreement(s), the entity may not issue qualifying preferred stock if the total net proceeds exceed this ratio.

No definition available.

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The maximum length of time for which interest payments on the convertible debentures may be deferred without giving rise to an event of default.

No definition available.

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The minimum number of consecutive interest periods for which interest payments may be deferred pursuant to an optional deferral provision under the note agreement(s).

No definition available.

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The minimum number of trading days within a specified time period that the closing sale price of the entity's common stock exceeds the prevailing conversion price of the debentures by a specified percentage.

No definition available.

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The percentage calculated as the average closing price of the entity's common stock times the number of the entity's outstanding shares of common stock. The average price is determined over a specified period ending before the issuance of the common stock or warrants being sold, and the number of outstanding shares is determined as of the date of the entity's most recent publicly released financial statements.

No definition available.

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The maximum period, in business days, after payment of interest on debentures that was not deferred, in which the entity must begin reasonable commercial efforts to sell qualifying securities to unaffiliated persons pursuant to the optional deferral provision under the note agreement(s).

No definition available.

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The period immediately prior to an election to convert debentures during which the average price of shares traded is determined for the purpose of calculating the conversion rate.

No definition available.

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The principal amount of notes used in the determination of the initial conversion rate, which is subject to adjustment.

No definition available.

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The price per share of the conversion feature embedded in the debt instrument.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

No definition available.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

No definition available.

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Interest rate of advances made and reported by Federal Home Loan Bank (FHLBank).

No definition available.

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Amount of cash paid for interest. Includes, but is not limited to, payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
-Paragraph 25
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-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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