Condensed Consolidated Balance Sheets - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Document Period End Date	Mar. 31, 2020
Assets
Fixed maturities, available-for-sale, at fair value (amortized cost $2,051.8 and $2,080.0, respectively)	$ 2,128.3	$ 2,127.9
Equity securities	275.7	395.2
Other invested assets	54.6	69.7
Other invested assets, at cost	12.5	6.5
Notes receivable from affiliate	70.0	70.0
Total investments	2,541.1	2,669.3
Cash and cash equivalents	126.6	78.0
Accrued investment income and other assets	33.2	31.7
Deferred policy acquisition costs (affiliated net assumed $21.8 and $20.2, respectively)	113.3	111.1
Reinsurance recoverable on losses and loss expenses payable	39.7	13.6
Prepaid reinsurance premiums	7.9	7.5
Due from Affiliates	22.5	21.5
Current federal income taxes	6.7	6.3
Net deferred federal income taxes	64.9	42.2
Property and equipment, held for sale	4.2	4.2
Total assets	2,960.1	2,985.4
Liabilities and Stockholders’ Equity
Losses and loss expenses payable (affiliated net assumed $457.3 and $500.8, respectively)	1,086.6	1,066.5
Unearned premiums (affiliated net assumed $126.3 and $116.7, respectively)	665.7	649.2
Notes payable (affiliates $15.2 and $15.2, respectively)	182.1	122.0
Pension and postretirement benefits	71.5	72.9
Other liabilities (affiliated net assumed $10.7 and $19.5, respectively)	87.5	114.9
Total liabilities	2,093.4	2,025.5
Stockholders’ equity:
Common stock, without par value. Authorized 100.0 shares; 50.6 and 50.4 shares issued, respectively, at stated value of $2.50 per share	126.5	125.9
Treasury stock, 6.9 and 6.9 shares, respectively, at cost	(118.4)	(117.5)
Additional paid-in capital	209.1	206.7
Accumulated other comprehensive loss	(13.7)	(37.9)
Retained earnings	663.2	782.7
Total stockholders’ equity	866.7	959.9
Total liabilities and stockholders’ equity	2,960.1	2,985.4
Class A Preferred Stock [Member]
Stockholders’ equity:
Preferred stock value	0.0	0.0
Class B Preferred Stock [Member]
Stockholders’ equity:
Preferred stock value	$ 0.0	$ 0.0