CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash Flows from Operating Activities
Net Income	$ 793.0	$ 1,100.3	$ 523.4
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Change in Receivables	242.9	37.5	(4.7)
Change in Deferred Acquisition Costs	29.9	(48.7)	(102.5)
Change in Insurance Reserves and Liabilities	1,610.0	376.1	1,193.1
Change in Income Taxes	(31.3)	248.2	(39.1)
Change in Other Accrued Liabilities	160.1	51.3	(10.1)
Non-cash Components of Net Investment Income	(120.5)	(237.9)	(211.1)
Net Realized Investment (Gain) Loss	(1,199.1)	23.2	39.5
Depreciation	113.6	110.1	101.4
Cash Related to Reinsurance Agreement	(1,084.6)	0.0	0.0
Other, Net	83.5	81.5	46.6
Net Cash Provided by Operating Activities	597.5	1,741.6	1,536.5
Cash Flows from Investing Activities
Proceeds from Sales of Fixed Maturity Securities	990.8	955.2	642.5
Proceeds from Maturities of Fixed Maturity Securities	2,052.4	2,401.0	2,815.4
Proceeds from Sales and Maturities of Other Investments	237.0	363.5	454.0
Purchase of Fixed Maturity Securities	(3,169.6)	(4,022.4)	(3,861.7)
Purchase of Other Investments	(440.6)	(568.5)	(623.2)
Net Sales (Purchases) of Short-term Investments	(133.1)	(267.6)	200.5
Net Increase (Decrease) in Payables for Collateral on Investments	314.5	(104.1)	(268.1)
Acquisition of Business (Net of Cash Acquired)	0.0	0.0	(145.4)
Net Purchases of Property and Equipment	(119.1)	(150.9)	(144.1)
Other, Net	0.0	(0.3)	0.0
Net Cash Used by Investing Activities	(267.7)	(1,393.5)	(930.1)
Cash Flows from Financing Activities
Short-term Debt Repayment	(400.0)	0.0	(200.0)
Issuance of Long-term Debt	494.1	841.9	290.7
Long-term Debt Repayment	(80.0)	(493.1)	(60.0)
Cost Related to Early Retirement of Debt	0.0	25.9	0.0
Issuance of Common Stock	4.4	6.1	4.6
Repurchase of Common Stock	0.0	(400.3)	(356.2)
Dividends Paid to Stockholders	(231.9)	(229.2)	(215.6)
Cash Received Related to Active Life Volatility Cover Agreement	62.1	0.0	0.0
Other, Net	(65.6)	(57.5)	(53.3)
Net Cash Used by Financing Activities	(216.9)	(358.0)	(589.8)
Net Increase (Decrease) in Cash and Bank Deposits	112.9	(9.9)	16.6
Cash and Bank Deposits at Beginning of Year	84.1	94.0	77.4
Cash and Bank Deposits at End of Year	$ 197.0	$ 84.1	$ 94.0

Cash Received Related to Active Life Volatility Cover Agreement Reinsurance Agreement

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Net operating cash related to reinsurance agreement

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of increase (decrease) in deferred policy acquisition cost.

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The aggregate net amount of depreciation, amortization, and accretion recognized during an accounting period. As a noncash item, the net amount is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of realized and unrealized gain (loss) on investment.

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The increase (decrease) during the period in the amount due for taxes based on the reporting entity's earnings or attributable to the entity's income earning process (business presence) within a given jurisdiction.

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