Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Assets
Fixed maturities, amortized cost	$ 521,017	$ 494,561
Equity securities, cost	130,751	64,902
Limited partnerships, affiliated	43,586	44,038
Account receivable, allowance	484	542
Property and equipment, accumulated depreciation	$ 16,614	$ 15,328
Class A Voting [Member]
Shareholders' equity:
Common stock, shares authorized (in shares)	3,000,000	3,000,000
Common stock, shares outstanding (in shares)	2,623,109	2,623,109
Class B Non-voting [Member]
Shareholders' equity:
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, shares outstanding (in shares)	12,423,518	12,460,900