Capital Stock and Derivative Instruments - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended	3 Months Ended		12 Months Ended
	Jun. 01, 2016	Jan. 05, 2015	Mar. 19, 2012	Jun. 30, 2017	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016		Dec. 31, 2015	May 15, 2015	May 11, 2015	May 10, 2015	Jan. 30, 2014
Capital Stock Distribution [Line Items]
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					$ 0.00001		$ 0.00001				$ 0.00001	$ 0.00001
Preferred stock, par value					$ 0.00001						$ 0.00001	$ 0.00001
Conversion of shares											1
Warrants to purchase in aggregate, shares													61,400,000
Warrants expiration period					5 years
Maximum percent of the voting shares of the emerging entity immediately prior to the confirmation of reorganization					50.00%
Registration right period					180 days
Escrow deposit		$ 598,500			$ 573,900		$ 572,900
Derivative asset - embedded conversion feature					98,680		80,651	[1]
Changes in fair value					$ 18,029	$ 55,875
Award vesting period					3 years
Number of additional Restricted Stock Awards Outstanding, Restricted stock awards granted					1,015,874
Unamortized value of unvested restricted share grants					$ 7,129		$ 7,700
Equity-based compensation					$ 140	164
Per share of unvested shares of common stock					$ 0.0001
Vested number of shares					41,188
Common stock, shares issued					206,380,800		206,380,800
Common stock, shares outstanding					206,380,800		206,380,800
Warrants to purchase common stock, Issued					61,400,000		61,400,000
Warrants to purchase common stock, outstanding					61,400,000		61,400,000
Scenario Forecast [Member]
Capital Stock Distribution [Line Items]
Expected increase in additional paid in capital due to early vesting of equity shares				$ 83
Expected increase in share based compensation due to early vesting of equity shares				$ 83
Exec Grants [Member]
Capital Stock Distribution [Line Items]
Share price										$ 2.76
Restricted stock fair value					$ 6,600
Restricted stock price per share					$ 1.45
Chief Executive Officer [Member]
Capital Stock Distribution [Line Items]
Number of additional Restricted Stock Awards Outstanding, Restricted stock awards granted					507,937
Restricted stock award [Member]
Capital Stock Distribution [Line Items]
Amount of restricted stock grants	$ 500
Share price	$ 2.35
Unvested shares					6,380,800		6,380,800		6,168,035
Number of Restricted Stock Awards Outstanding, Restricted stock awards granted	212,765				0		212,765
Restricted stock award [Member] | Exec Grants [Member]
Capital Stock Distribution [Line Items]
Amount of restricted stock grants										$ 9,800
Restricted shares subject to repurchase [Member]
Capital Stock Distribution [Line Items]
Unvested shares					3,761,496		4,039,591		4,197,396
Number of Restricted Stock Awards Outstanding, Restricted stock awards granted							212,765
Minimum [Member]
Capital Stock Distribution [Line Items]
Preferred stock liquidation preference per share					$ 10.00
Minimum [Member] | Exec Grants [Member]
Capital Stock Distribution [Line Items]
Preferred stock additional shares conversion price					1.75
Restricted stock price per share					1.75
Maximum [Member] | Exec Grants [Member]
Capital Stock Distribution [Line Items]
Preferred stock additional shares conversion price					2.25
Convertible Series A Preferred Stock [Member]
Capital Stock Distribution [Line Items]
Preferred stock, par value					$ 0.00001		$ 0.00001
Preferred stock, shares issued					1,000,000		1,000,000						1,000,000
Purchase price of convertible preferred stock maximum limit								[1]					$ 11,100
Preferred stock liquidation preference					The Series A Preferred Stock has rights substantially similar to those associated with WMIH’s common stock, with the exception of a liquidation preference, conversion rights and customary anti-dilution protections. The Series A Preferred Stock has a liquidation preference equal to the greater of (i) $10.00 per one million shares of Series A Preferred Stock plus declared but unpaid dividends on such shares and (ii) the amount that the holder would be entitled to in a relevant transaction had the Series A Preferred Stock been converted to common stock of WMIH.
Convertible preferred stock conversion price					$ 1.10
Preferred deemed dividend					$ 9,500
Preferred stock, shares outstanding					1,000,000		1,000,000
Redeemable Convertible Series B Preferred Stock [Member]
Capital Stock Distribution [Line Items]
Preferred stock, shares issued		600,000			600,000		600,000
Preferred stock dividend rate calculated on interest rate		3.00%
Preferred stock, redemption date					Jan. 05, 2018
Preferred stock, shares outstanding					600,000		600,000		600,000
Preferred stock, redemption amount					$ 600,000
Number of trading periods					20 days
Conversion ceiling price of common stock					$ 2.25
Conversion floor price of common stock					$ 1.75
Derivative liability - embedded conversion feature		$ 66,200				65,000
Derivative asset - embedded conversion feature					$ 98,700		$ 80,700
Changes in fair value					$ 18,000	$ (55,900)	$ 201,500
Share price										$ 2.25
Redeemable Convertible Series B Preferred Stock [Member] | Maximum [Member]
Capital Stock Distribution [Line Items]
Conversion ceiling price of common stock					$ 2.25
Common Stock [Member]
Capital Stock Distribution [Line Items]
Issuance of common stock, Shares			200,000,000
Warrant One [Member]
Capital Stock Distribution [Line Items]
Warrants to purchase common stock													30,700,000
Warrants to purchase common stock, exercise price													$ 1.32
Warrant Two [Member]
Capital Stock Distribution [Line Items]
Warrants to purchase common stock													30,700,000
Warrants to purchase common stock, exercise price													$ 1.43

[1] Balances derived from audited financial statements as of December 31, 2016.