Investments - Fixed-maturity securities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2018
Investments
Fixed maturity securities Due after one year through three years Amortized Cost	$ 17,877
Fixed maturity securities Due after three years through five years Amortized Cost	0
Fixed maturity securities Due after five years through ten years Amortized Cost	7,884
Fixed maturity securities Total fixed maturity securities Amortized Cost	25,761	$ 15,072
Fixed maturity securities Due after one year through three years Fair Value	12,941
Fixed maturity securities Due after three years through five years Fair Value	0
Fixed maturity securities Due after five years through ten years Fair Value	7,452
Fixed maturity securities Total fixed maturity securities Fair Value	$ 20,393	$ 13,381