OTHER ASSETS, NET - Schedule of other assets, net (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets
Less accumulated depreciation and amortization	$ (57.2)	$ (57.2)	$ (193.2)
Data processing software, net	29.7	29.7	34.5
Other assets	21.9	21.9	28.4
Data processing software and other assets, net	51.6	51.6	62.9
Provision for uncollectibility of promissory notes receivable	23.4	23.4
Notes receivable	9.2	9.2	20.3
Amortization		138.6	160.0	$ 142.9
Options
Finite-Lived Intangible Assets
Amortization		15.3	16.8
Software development work in progress
Finite-Lived Intangible Assets
Software	2.6	2.6	8.7
Data processing software
Finite-Lived Intangible Assets
Software	84.3	84.3	219.0
Amortization		$ 13.5	$ 18.9	$ 17.9
Data processing software \| Options
Finite-Lived Intangible Assets
Loss on disposal of data processing software	$ 4.5

Amount of allowance for credit loss of accounts and financing receivables. Includes, but is not limited to, notes and loan receivable.

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