INCOME TAXES. (Provision for Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
U.S. federal	$ 490.9	$ 484.2	$ 708.1
State and local	135.9	138.7	131.0
Foreign	18.3	28.5	13.1
Deferred income taxes (benefits)	33.3	(35.5)	71.7
Total	$ 678.4	$ 615.9	$ 923.9

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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