SIGNIFICANT ACCOUNTING POLICIES - New Accounting Pronouncements (Details) - USD ($) $ in Millions	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
New accounting guidance, cumulative effect	$ 8,243.0		$ 9,993.7
Cumulative Effect, Period of Adoption, Adjustment \| Accounting Standards Update 2016-13
New accounting guidance, cumulative effect		$ 4.3

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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