Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Operating activities
Net cash provided by operating activities	$ 2,848.4	$ 2,009.7
Investing activities
Fixed maturities available-for-sale and equity securities with intent to hold: Purchases	(8,430.3)	(15,369.6)
Fixed maturities available-for-sale and equity securities with intent to hold: Sales	4,007.5	11,491.8
Fixed maturities available-for-sale and equity securities with intent to hold: Maturities	3,874.4	5,223.5
Mortgage loans acquired or originated	(1,610.9)	(3,183.9)
Mortgage loans sold or repaid	1,681.5	2,248.3
Real estate acquired	(137.6)	(138.9)
Real estate sold	131.9	288.4
Net purchases of property and equipment	(74.1)	(86.3)
Net change in other investments	(574.3)	16.7
Net cash provided by (used in) investing activities	(1,131.9)	490.0
Financing activities
Issuance of common stock	43.4	102.0
Accelerated share repurchase		(33.9)
Acquisition of treasury stock	(489.7)	(1,410.7)
Payments for financing element derivatives	(31.7)	(38.9)
Purchase of subsidiary shares from noncontrolling interest	(2.8)	(9.2)
Dividends to common stockholders	(466.5)	(486.1)
Issuance of long-term debt	691.5
Principal repayments of long-term debt	(764.0)	(301.4)
Net proceeds from (repayments of) short-term borrowings	(58.1)	(4.9)
Investment contract deposits	6,709.9	5,921.7
Investment contract withdrawals	(7,084.0)	(5,435.0)
Net increase (decrease) in banking operation deposits	(548.3)	1,104.7
Other	0.1	(0.4)
Net cash provided by (used in) financing activities	(2,000.2)	(592.1)
Net increase (decrease) in cash and cash equivalents	(283.7)	1,907.6
Cash and cash equivalents at beginning of period	4,848.0	2,332.0
Cash and cash equivalents at end of period	4,564.3	4,239.6
Asset changes resulting from deconsolidation of residential whole loan securitizations:
Decrease in mortgage loans	(294.5)
Increase in fixed maturities, available-for-sale	227.4
Increase in fixed maturities, trading	$ 8.4
Assets transferred in kind for settlement to reinsurer		$ (428.5)

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