Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue:
Premium	$ 3,595,134	$ 3,421,906	$ 3,282,935
Net investment income	910,459	882,512	847,885
Realized gains (losses)	20,621	(1,804)	23,611
Other income	1,318	1,137	1,142
Total revenue	4,527,532	4,303,751	4,155,573
Benefits and expenses:
Life policyholder benefits	1,638,053	1,591,790	1,558,261
Health policyholder benefits	687,764	649,188	633,778
Other policyholder benefits	31,532	34,264	35,836
Total policyholder benefits	2,357,349	2,275,242	2,227,875
Amortization of deferred policy acquisition costs	551,726	516,690	490,403
Commissions, premium taxes, and non-deferred acquisition costs	298,047	278,487	264,860
Other operating expense	304,825	279,585	257,255
Interest expense	84,306	90,076	84,532
Total expenses	3,596,253	3,440,080	3,324,925
Income before income taxes	931,279	863,671	830,648
Income tax benefit (expense)	(170,397)	(162,161)	627,615
Income from continuing operations	760,882	701,510	1,458,263
Loss (income) from discontinued operations, net of income taxes	(92)	(44)	(3,769)
Net income	$ 760,790	$ 701,466	$ 1,454,494
Basic net income (loss) per common share:
Continuing operations (in dollars per share)	$ 6.97	$ 6.22	$ 12.53
Discontinued operations (in dollars per share)	0	0	(0.03)
Total basic net income per common share (in dollars per share)	6.97	6.22	12.50
Diluted net income (loss) per common share:
Continuing operations (in dollars per share)	6.83	6.09	12.26
Discontinued operations (in dollars per share)	0	0	(0.04)
Total diluted net income per common share (in dollars per share)	$ 6.83	$ 6.09	$ 12.22
Life premium
Revenue:
Premium	$ 2,517,784	$ 2,406,555	$ 2,306,547
Health premium
Revenue:
Premium	1,077,346	1,015,339	976,373
Other premium
Revenue:
Premium	$ 4	$ 12	$ 15