Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, authorized shares	0	0
Preferred stock, issued shares	0	0
Preferred stock, outstanding shares	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, authorized shares	50,000,000	50,000,000
Common stock, issued shares	43,049,917	43,029,845
Common stock, outstanding shares	43,231,184	42,984,578
Treasury stock	212,083	212,083
Schedule of Available-for-sale Securities
Other investments, cost	$ 11,599
Fixed Maturities
Schedule of Available-for-sale Securities
Fixed maturities, cost	852,252	$ 874,445
Other Long-term Investments
Schedule of Available-for-sale Securities
Other investments, cost	$ 11,599	$ 8,288

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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