Face amount or stated value per share of common stock.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

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(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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- Definition

Date the plan of reorganization is effective, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56451-112766

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

+ Details

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

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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.

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The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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- Definition

The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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- Definition

Approved amount for distribution.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Number of insurers.

+ References

No definition available.

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The Company and its Subsidiaries - Additional Information (Detail)	9 Months Ended	12 Months Ended
	Sep. 30, 2017 Insurers $ / shares shares	Dec. 31, 2016 $ / shares shares	Sep. 13, 2017 USD ($)	Dec. 31, 2015 shares	May 11, 2015 $ / shares shares	May 10, 2015 $ / shares shares	Jan. 05, 2015 shares	Jan. 30, 2014 shares
Related Party Transaction [Line Items]
Plan Effective Date	Mar. 19, 2012
Common stock, shares authorized	3,500,000,000	3,500,000,000			3,500,000,000	500,000,000
Preferred stock, shares authorized	10,000,000				10,000,000	5,000,000
Common stock, par value \| $ / shares	$ 0.00001	$ 0.00001			$ 0.00001	$ 0.00001
Convertible preferred stock, par value \| $ / shares	$ 0.00001				$ 0.00001	$ 0.00001
Common stock, shares issued	206,714,132	206,380,800
Common stock, shares outstanding	206,714,132	206,380,800
Distribution from WMMRC to WMIH Deposited in Collateral Account [Member] \| Maximum [Member]
Related Party Transaction [Line Items]
Approved amount for distribution \| $			$ 10,700,000
WMMRC [Member]
Related Party Transaction [Line Items]
Number of primary mortgage insurers \| Insurers	7
Convertible Series A Preferred Stock [Member]
Related Party Transaction [Line Items]
Convertible preferred stock, par value \| $ / shares	$ 0.00001	$ 0.00001
Convertible preferred stock, shares issued	1,000,000	1,000,000						1,000,000
Convertible preferred stock, shares outstanding	1,000,000	1,000,000
Redeemable Convertible Series B Preferred Stock [Member]
Related Party Transaction [Line Items]
Preferred stock, shares issued	600,000	600,000					600,000
Preferred stock, shares outstanding	600,000	600,000		600,000
Preferred stock dividend rate	3.00%	3.00%