Servicing of Residential Loans - Schedule of Servicing Rights Carried at Amortized Cost (Detail) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Feb. 09, 2018	Dec. 31, 2018	Dec. 31, 2017
Servicing Asset at Amortized Cost, Balance [Roll Forward]
Amortization	$ (2,187)	$ (7,531)	$ (21,954)
Mortgage Loan Class [Member]
Servicing Asset at Amortized Cost, Balance [Roll Forward]
Balance at beginning of the period	54,466	57,148	74,621
Fresh start accounting adjustments	4,221
Amortization	(944)	(9,022)	(8,423)
Impairment	(595)	(3,167)	(11,732)
Disposals	0	(3,744)	0
Balance at end of the period	57,148	41,215	54,466
Reverse Loan Class [Member]
Servicing Asset at Amortized Cost, Balance [Roll Forward]
Balance at beginning of the period	4,011	4,542	5,505
Fresh start accounting adjustments	1,211
Amortization	(148)	(1,201)	(1,494)
Impairment	(532)	(346)	0
Disposals	0	(133)	0
Balance at end of the period	$ 4,542	$ 2,862	$ 4,011