Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Cost or Amortized Cost	$ 1,612,626	$ 1,659,760
Available-for-sale securities, allowance for credit losses	8	0
Trading securities, amortized cost	12,258	11,941
Equity securities, cost	61,467	67,529
Allowance for doubtful accounts	812	1,239
Property and equipment accumulated depreciation	54,145	50,183
Reinsurance receivables and recoverables, allowance for credit losses	$ 241	$ 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)	25,031,234	25,015,963
Common stock, shares outstanding (in shares)	25,031,234	25,015,963