Capital Stock - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended	0 Months Ended	1 Months Ended	0 Months Ended	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Apr. 28, 2015	Jan. 30, 2015	Jan. 05, 2015	Mar. 15, 2015	Mar. 19, 2012	Jan. 30, 2014	Dec. 31, 2013
Capital Stock Distribution [Line Items]
Common stock, shares authorized	500,000,000		500,000,000
Preferred stock, shares authorized	5,000,000		5,000,000
Common stock, par value	$ 0.00001		$ 0.00001
Preferred stock, par value	$ 0.00001		$ 0.00001
Warrants to purchase in aggregate, shares									61,400,000
Convertible preferred stock conversion price	$ 1.10
Preferred stock liquidation preference per share	$ 10.00
Preferred deemed dividend		$ 9,455,000
Warrants expiration period	5 years
Maximum percent of the voting shares of the emerging entity immediately prior to the confirmation of reorganization	50.00%				42.50%			50.00%
Registration right period	180 days
Preferred stock dividend rate	3.00%
Escrow deposit						598,500,000
Amount of restricted stock grants	0		600,000
Amount of additional restricted stock grants issued			700,000
Award vesting period	3 years
Unamortized value of unvested restricted share grant	848,000		1,200,000
Equity-based compensation	384,000	129,000
Per share of unvested shares of common stock	$ 0.0001
Vested number of shares	190,070
Vested number of shares, outstanding	113,146
Expected increase in additional paid in capital due to early vesting of equity shares	182,000
Expected increase in share based compensation due to early vesting of equity shares	182,000
Common stock, shares outstanding	202,343,245		202,343,245
Warrants to purchase common stock, outstanding	61,400,000		61,400,000
Subsequent Event [Member]
Capital Stock Distribution [Line Items]
Common stock, par value				$ 0.00001
Preferred stock, par value				$ 0.00001
Amount of restricted stock grants				269,234
Amount of additional restricted stock grants issued				700,000
Restricted shares subject to repurchase [Member]
Capital Stock Distribution [Line Items]
Unvested shares	562,676		1,343,764							1,456,987
Series A Convertible Preferred Stock [Member]
Capital Stock Distribution [Line Items]
Preferred stock, shares issued	1,000,000		1,000,000						1,000,000
Purchase price of convertible preferred stock maximum limit									11,100,000
Preferred stock liquidation preference	The Series A Preferred Stock has rights substantially similar to those associated with WMIHC’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 WMIHC.
Preferred stock, shares outstanding	1,000,000		1,000,000
Convertible Preferred Stock [Member]
Capital Stock Distribution [Line Items]
Expiration of right to participating into future offering					Jan. 30, 2017
Preferred stock participation right					Additionally, until January 30, 2017, the Series A Holders will have the right to purchase up to 50% of any future equity rights offerings or other equity issuance by WMIHC on the same terms as the equity issued to other investors in such transactions, in an aggregate amount of such offerings and issuances by WMIHC of up to $1.0 billion
Convertible Preferred Stock [Member] | Maximum [Member]
Capital Stock Distribution [Line Items]
Maximum percent of the voting shares of the emerging entity immediately prior to the confirmation of reorganization					50.00%
Percentage of rights vest with preferred shareholders to future offering					50.00%
Preferred stock participation value					1,000,000,000
Series B Preferred Stock [Member]
Capital Stock Distribution [Line Items]
Common stock, par value	$ 1.75
Preferred stock, par value						$ 0.00001
Preferred stock, shares issued	600,000		0			600,000
Preferred stock liquidation preference per share						$ 1,000
Preferred stock dividend rate						3.00%
Number of trading periods	20 days
Aggregate fair value	59,000,000		0			66,200,000
Changes in Fair Value							$ 7,200,000
Preferred stock, shares outstanding	600,000		0
Series B Preferred Stock [Member] | Maximum [Member]
Capital Stock Distribution [Line Items]
Common stock, par value	$ 2.25
Series B Convertible Preferred Stock [Member]
Capital Stock Distribution [Line Items]
Preferred stock, shares outstanding	600,000		0
Common Stock [Member]
Capital Stock Distribution [Line Items]
Issuance of common stock, Shares								200,000,000
Common stock, shares outstanding	202,343,245		202,343,245							201,842,351
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