BUSINESS ACQUISITIONS - Schedule of Unaudited Supplemental Pro Forma Financial Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Caliber Home Loans Inc
Pro Forma (in millions)
Revenues	$ 5,422.7	$ 4,453.4
Income (loss) before income taxes	1,258.6	(529.9)
Ditech Acquisition
Pro Forma (in millions)
Revenues			$ 1,104.0
Income (loss) before income taxes			552.8
Guardian
Pro Forma (in millions)
Income (loss) before income taxes			$ 651.5
Genesis
Pro Forma (in millions)
Revenues	3,643.4	1,693.0
Income (loss) before income taxes	$ 981.8	$ (1,316.1)