STATUTORY INFORMATION (BASED ON NON-GAAP MEASURES) - SCHEDULE OF STATUTORY ACCOUNTING PRACTICES (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Insurance [Abstract]
Statutory capital and surplus	$ 1,696.6	$ 1,652.8
Asset valuation reserve	295.9	233.3
Interest maintenance reserve	420.1	425.0
Total	$ 2,412.6	$ 2,311.1