The sum of insurance premiums earned, premiums earned on the income statement for all insurance contracts after subtracting any amounts ceded to another insurer and adding premiums assumed from other insurers, plus contract charges earned on investment and universal life-type contracts.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Segment Information - Summarized Financial Information by Segment (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Summarized financial information for these segments
Insurance premiums and contract charges earned	$ 240,392	$ 239,681	$ 208,096	$ 209,785	$ 201,905	$ 206,820	$ 205,610	$ 202,998	$ 204,328	$ 198,935	$ 195,718	$ 195,722	$ 897,954	$ 817,333	$ 794,703
Net investment income													365,064	376,507	373,630
Net income (loss)	33,001	$ 25,454	$ 93,822	$ 32,166	(20,257)	$ 12,528	$ 5,917	$ 20,155	125,329	$ 26,551	$ 2,261	$ 15,318	184,443	18,343	169,459
Assets	12,478,704				11,031,896				11,198,340				12,478,704	11,031,896	11,198,340
Intersegment eliminations
Summarized financial information for these segments
Net investment income													(1,503)	(772)	(815)
Assets	(64,072)				(41,800)				(42,482)				(64,072)	(41,800)	(42,482)
Property and Casualty
Summarized financial information for these segments
Insurance premiums and contract charges earned													683,454
Property and Casualty \| Operating Segments
Summarized financial information for these segments
Insurance premiums and contract charges earned														665,734	648,263
Net investment income													41,740	40,104	36,178
Net income (loss)													54,359	(14,243)	17,790
Assets	1,327,099				1,236,362				1,217,394				1,327,099	1,236,362	1,217,394
Supplemental
Summarized financial information for these segments
Insurance premiums and contract charges earned													65,815
Net investment income													7,480
Net income (loss)													17,989
Assets	747,602												747,602
Retirement
Summarized financial information for these segments
Insurance premiums and contract charges earned													29,083
Retirement \| Operating Segments
Summarized financial information for these segments
Insurance premiums and contract charges earned														31,269	28,003
Net investment income													245,475	262,634	261,994
Net income (loss)													(4,867)	41,736	88,473
Assets	8,330,127				7,866,969				8,063,912				8,330,127	7,866,969	8,063,912
Life
Summarized financial information for these segments
Insurance premiums and contract charges earned													119,602
Life \| Operating Segments
Summarized financial information for these segments
Insurance premiums and contract charges earned														120,330	118,437
Net investment income													71,957	74,399	76,195
Net income (loss)													17,574	18,754	77,595
Assets	1,964,993				1,821,351				1,815,732				1,964,993	1,821,351	1,815,732
Corporate and Other
Summarized financial information for these segments
Net investment income													(85)	142	78
Net income (loss)													99,388	(27,904)	(14,399)
Assets	$ 172,955				$ 149,014				$ 143,784				$ 172,955	$ 149,014	$ 143,784