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Federal Income Taxes Federal Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Tax at statutory rate (21% in 2020 and 2019)	$ 3,359	$ 15,476
Tax-advantaged interest	(1,214)	(1,253)
Dividends received deduction	(55)	(83)
Executive compensation	351	473
Stock-based compensation	(1,881)	(2,635)
Other	201	368
Federal income tax expense	$ 761	$ 12,346
Effective Income Tax Rate Reconciliation, Percent	4.80%	16.80%
Net realized and unrealized investment (losses) gains	$ (44,666)	$ 13,451
Deferred Income Tax Assets, Net	$ 43,099		$ 6,776

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