Fair Value Measurements and Derivative Instruments (Available-For-Sale Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost	$ 247,866	$ 260,145
Gross unrealized gains		11
Gross unrealized losses	(44,024)	(51,890)
Debt securities	203,842	208,266
Government and related securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost	35,048	35,744
Gross unrealized gains		11
Gross unrealized losses	(7,018)	(8,210)
Debt securities	28,030	27,545
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost	65,008	66,300
Gross unrealized gains		0
Gross unrealized losses	(10,678)	(13,981)
Debt securities	54,330	52,319
Commingled fixed income securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost	1,788	1,749
Gross unrealized gains		0
Gross unrealized losses	(207)	(229)
Debt securities	1,581	1,520
Mortgage-backed / asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost	146,022	156,352
Gross unrealized gains		0
Gross unrealized losses	(26,121)	(29,470)
Debt securities	$ 119,901	$ 126,882