CONSOLIDATED STATEMENT OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Revenues:
Insurance policy income	$ 2,499.8	$ 2,523.4	$ 2,511.3
Net investment income:
General account assets	1,179.0	1,140.2	1,079.0
Policyholder and other special-purpose portfolios	(163.1)	280.5	143.5
Investment gains (losses):
Realized investment gains (losses)	(17.9)	21.3	(18.4)
Other investment gains (losses)	(117.5)	(2.2)	(17.8)
Total investment gains (losses)	(135.4)	19.1	(36.2)
Fee revenue and other income	196.5	159.0	123.5
Total revenues	3,576.8	4,122.2	3,821.1
Benefits and expenses:
Insurance policy benefits	1,658.3	2,190.7	2,157.9
Interest expense	137.0	95.4	108.8
Amortization	309.6	281.1	268.1
Other operating costs and expenses	954.6	987.3	942.0
Total benefits and expenses	3,059.5	3,554.5	3,476.8
Income before income taxes	517.3	567.7	344.3
Income tax expense (benefit):
Tax expense on period income	120.5	126.7	76.5
Valuation allowance for deferred tax assets and other tax items	0.0	0.0	(34.0)
Net income	$ 396.8	$ 441.0	$ 301.8
Basic:
Weighted average shares outstanding (in shares)	115,733	128,400	142,096
Net income (in USD per share)	$ 3.43	$ 3.43	$ 2.12
Diluted:
Weighted average shares outstanding (in shares)	117,717	131,126	143,164
Net income (in USD per share)	$ 3.37	$ 3.36	$ 2.11