Investments in debt and equity securities (Tables)

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Investments in debt and equity securities

The total fair values of the Company's investments in debt and equity securities as of December 31 are detailed below:

	2023	2022
	(in $ thousands)
Investments in:
Debt securities	610,236	611,934
Equity securities	69,700	98,149
	679,936	710,083

Net investment gains and losses recognized for the years ended December 31 related to investments in equity securities are follows:

	2023	2022	2021
	(in $ thousands)
Total net investment gains (losses) recognized on equity securities during the period	3,044	(2,151)	19,351
Less: Net realized gains on equity securities sold during the period	975	395	1,631
Net unrealized investment gains (losses) recognized on equity securities still held at December 31	2,069	(2,546)	17,720

Amortized costs and fair values

The amortized costs and fair values of investments in debt securities as of December 31, are as follows:

	2023		2022
	Amortized costs	Fair values	Amortized costs	Fair values
	(in $ thousands)
Municipal	22,201	22,031	30,104	29,835
Corporate	242,656	231,474	272,362	254,316
Foreign	332,723	323,391	315,184	299,137
U.S. Treasury Bonds	33,714	33,340	29,078	28,646
	631,294	610,236	646,728	611,934

Proceeds from sales of investments in securities for the years ended December 31 are as follows:

	2023	2022	2021
	(in $ thousands)
Proceeds from sales of debt securities	21,909	65,827	68,450
Proceeds from sales of equity securities	38,548	868	843
Total proceeds from sales of investments in securities	60,457	66,695	69,293

Gross unrealized gains and losses

Gross unrealized gains and losses on investments in debt securities at December 31, were:

	2023		2022
	Gains	Losses	Gains	Losses
	(in $ thousands)
Municipal	—	170	3	272
Corporate	764	11,946	489	18,535
Foreign	1,765	11,097	165	16,212
U.S. Treasury Bonds	106	480	21	453
	2,635	23,693	678	35,472

Debt securities according to contractual terms

Debt securities at December 31, 2023 mature, according to their contractual terms, as follows (actual maturities may differ due to call or prepayment rights):

	Amortized costs	Fair values
	(in $ thousands)
In one year or less	101,047	99,855
After one year through five years	344,370	330,077
After five years through ten years	173,408	168,804
After ten years	12,469	11,500
	631,294	610,236

Gross unrealized losses on investments and fair values of related securities

Gross unrealized losses on investments in debt securities and the fair values of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at December 31, 2023, were:

	Less than 12 months		More than 12 months		Total
	Losses	Fair values	Losses	Fair values	Losses	Fair values
	(in $ thousands)
Municipal	50	13,022	120	8,383	170	21,405
Corporate	68	4,808	11,878	208,971	11,946	213,779
Foreign	472	31,918	10,625	216,135	11,097	248,053
U.S. Treasury Bonds	327	20,895	153	4,815	480	25,710
	917	70,643	22,776	438,304	23,693	508,947

Gross unrealized losses on investments in debt securities and the fair values of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at December 31, 2022, were:

	Less than 12 months		More than 12 months		Total
	Losses	Fair values	Losses	Fair values	Losses	Fair values
	(in $ thousands)
Municipal	262	27,491	10	67	272	27,558
Corporate	12,935	193,239	5,600	44,342	18,535	237,581
Foreign	7,608	186,221	8,604	101,294	16,212	287,515
U.S. Treasury Bonds	413	25,102	40	445	453	25,547
	21,218	432,053	14,254	146,148	35,472	578,201