STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Operating revenue
Operating revenue	$ 653,481	$ 638,742	$ 1,927,237	$ 1,880,558
Operating expenses
Operating expenses	557,256	532,835	1,654,132	1,591,919
Operating income	96,225	105,907	273,105	288,639
Investment income
Net investment income	7,030	8,652	22,772	25,199
Net realized investment gains	5,915	1,696	1,635	5,501
Net impairment losses recognized in earnings	(122)	(31)	(3,192)	(193)
Equity in earnings (losses) of limited partnerships	3,615	3,289	(2,419)	2,546
Total investment income	16,438	13,606	18,796	33,053
Interest expense, net	3	111	8	832
Other (expense) income	(964)	100	(1,588)	195
Income before income taxes	111,696	119,502	290,305	321,055
Income tax expense	22,480	25,333	59,786	63,821
Net income	$ 89,216	$ 94,169	$ 230,519	$ 257,234
Class A common stock
Earnings per share - Basic and diluted:
Common stock - basic (in dollars per share)	$ 1.92	$ 2.02	$ 4.95	$ 5.52
Common stock - diluted (in dollars per share)	$ 1.71	$ 1.80	$ 4.41	$ 4.92
Weighted average shares outstanding – Basic
Common stock - basic (in shares)	46,189,030	46,189,006	46,188,544	46,188,767
Weighted average shares outstanding – Diluted
Common stock - diluted (in shares)	52,310,429	52,325,125	52,312,588	52,317,275
Dividends declared per share
Common stock (in dollars per share)	$ 0.965	$ 0.90	$ 2.895	$ 2.70
Class B common stock
Earnings per share - Basic and diluted:
Common stock - basic (in dollars per share)	287	303	742	829
Common stock - diluted (in dollars per share)	$ 287	$ 303	$ 742	$ 828
Weighted average shares outstanding – Basic
Common stock - basic (in shares)	2,542	2,542	2,542	2,542
Weighted average shares outstanding – Diluted
Common stock - diluted (in shares)	2,542	2,542	2,542	2,542
Dividends declared per share
Common stock (in dollars per share)	$ 144.75	$ 135.00	$ 434.25	$ 405.00
Management fee revenue - policy issuance and renewal services, net
Operating revenue
Operating revenue	$ 484,551	$ 474,427	$ 1,412,096	$ 1,385,923
Operating expenses
Operating expenses	409,546	390,105	1,202,903	1,160,614
Management fee revenue - administrative services, net
Operating revenue
Operating revenue	14,910	14,430	44,494	42,576
Administrative services reimbursement revenue
Operating revenue
Operating revenue	147,710	142,730	451,229	431,305
Operating expenses
Operating expenses	147,710	142,730	451,229	431,305
Service agreement revenue
Operating revenue
Operating revenue	$ 6,310	$ 7,155	$ 19,418	$ 20,754