Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Cost or Amortized Cost	$ 1,720,291	$ 1,659,760
Available-for-sale securities, allowance for credit losses	5	0
Trading securities, amortized cost	0	11,941
Equity securities, cost	49,085	67,529
Allowance for doubtful accounts	687	1,239
Property and equipment, accumulated depreciation	55,141	50,183
Reinsurance receivables, allowance for credit losses	$ 190	$ 0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	75,000,000	75,000,000
Common stock, shares issued (in shares)	25,055,479	25,015,963
Common stock, shares outstanding (in shares)	25,055,479	25,015,963