Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Net Income	$ 64.0	$ 155.3
Other Comprehensive Income (Loss) Before Income Taxes:
Changes in Net Unrealized Holding Gains (Losses) on Investment Securities with:	(204.8)	162.8
Decrease in Net Unrecognized Postretirement Benefit Costs	0.7	0.6
Gain on Cash Flow Hedges	0.1	0.1
Other Comprehensive Income (Loss) Before Income Taxes	(204.0)	163.5
Other Comprehensive Income Tax Benefit (Expense)	42.8	(34.4)
Other Comprehensive Income (Loss)	(161.2)	129.1
Total Comprehensive Income (Loss)	(97.2)	284.4
No Credit Losses Recognized in Consolidated Statements of Income
Other Comprehensive Income (Loss) Before Income Taxes:
Changes in Net Unrealized Holding Gains (Losses) on Investment Securities with:	(201.9)	162.8
Credit Losses Recognized in Consolidated Statements of Income
Other Comprehensive Income (Loss) Before Income Taxes:
Changes in Net Unrealized Holding Gains (Losses) on Investment Securities with:	$ (2.9)	$ 0.0

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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