Investments (Schedule of Credit Ratings of Fixed Maturity Securities) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Marketable Securities [Line Items]
Total fixed maturities	$ 1,538,912	$ 1,214,635
Fixed Maturities
Marketable Securities [Line Items]
Total fixed maturities	$ 1,538,912	$ 1,214,635
Percent	100.00%	100.00%
Fixed Maturities | Investment grade
Marketable Securities [Line Items]
Total fixed maturities	$ 1,402,541	$ 1,115,885
Percent	91.10%	91.90%
Fixed Maturities | Investment grade | AAA and U.S. Government
Marketable Securities [Line Items]
Total fixed maturities	$ 200,014	$ 124,183
Percent	13.00%	10.20%
Fixed Maturities | Investment grade | AA
Marketable Securities [Line Items]
Total fixed maturities	$ 29,185	$ 815
Percent	1.90%	0.10%
Fixed Maturities | Investment grade | A
Marketable Securities [Line Items]
Total fixed maturities	$ 420,690	$ 371,371
Percent	27.30%	30.60%
Fixed Maturities | Investment grade | BBB
Marketable Securities [Line Items]
Total fixed maturities	$ 752,652	$ 619,516
Percent	48.90%	51.00%
Fixed Maturities | Non investment grade | BB and other
Marketable Securities [Line Items]
Total fixed maturities	$ 136,371	$ 98,750
Percent	8.90%	8.10%