Unaudited Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Millions	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Total Mr. Cooper Stockholders’ Equity	Non-controlling Interests	Treasury Share Amount
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total stockholders’ equity	$ 3,367	$ 1	$ 1,116	$ 2,879	$ 3,366	$ 1	$ (630)
Shares outstanding, beginning balance (in shares) at Dec. 31, 2021		73,777
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued / (surrendered) under incentive compensation plan (in shares)		856
Shares issued / (surrendered) under incentive compensation plan	(21)		(39)		(21)		18
Share-based compensation	17		17		17
Repurchase of common stock (in shares)		(2,982)
Repurchase of common stock	(135)				(135)		(135)
Net income	809			809	809	0
Shares outstanding, ending balance (in shares) at Jun. 30, 2022		71,651
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total stockholders’ equity	3,977	$ 1	1,085	3,537	3,976	1	(647)
Shares outstanding, beginning balance (in shares) at Mar. 31, 2022		73,906
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued / (surrendered) under incentive compensation plan (in shares)		6
Shares issued / (surrendered) under incentive compensation plan	0		0		0		0
Share-based compensation	9		9		9
Repurchase of common stock (in shares)		(2,261)
Repurchase of common stock	(100)				(100)		(100)
Net income	151			151	151	0
Shares outstanding, ending balance (in shares) at Jun. 30, 2022		71,651
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total stockholders’ equity	4,037	$ 1	1,094	3,688	4,036	1	(747)
Total stockholders’ equity	4,057	$ 1	1,104	3,802	4,057	0	(850)
Shares outstanding, beginning balance (in shares) at Dec. 31, 2022		69,266
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued / (surrendered) under incentive compensation plan (in shares)		877
Shares issued / (surrendered) under incentive compensation plan	(24)		(43)		(24)		19
Share-based compensation	13		13		13
Repurchase of common stock (in shares)		(3,295)
Repurchase of common stock	(146)				(146)		(146)
Net income	179			179	179	0
Shares outstanding, ending balance (in shares) at Jun. 30, 2023		66,848
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total stockholders’ equity	3,986	$ 1	1,066	3,839	3,986	0	(920)
Shares outstanding, beginning balance (in shares) at Mar. 31, 2023		68,053
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued / (surrendered) under incentive compensation plan (in shares)		7
Shares issued / (surrendered) under incentive compensation plan	0		0		0		0
Share-based compensation	8		8		8
Repurchase of common stock (in shares)		(1,212)
Repurchase of common stock	(57)				(57)		(57)
Net income	142			142	142	0
Shares outstanding, ending balance (in shares) at Jun. 30, 2023		66,848
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total stockholders’ equity	$ 4,079	$ 1	$ 1,074	$ 3,981	$ 4,079	$ 0	$ (977)