Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Fixed maturities, held-to-maturity securities, fair value	$ 150	$ 150
Fixed maturities, available-for-sale securities, amortized cost	1,811,473	1,516,610
Fixed maturities, trading securities, amortized cost	12,704	14,582
Equity securities, amortized cost	64,092	63,275
Allowance for doubtful accounts	988	1,255
Property and equipment accumulated depreciation	$ 53,603	$ 51,603
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)	25,043,967	24,916,806
Common stock, shares outstanding (in shares)	25,043,967	24,916,806