Fair Value Measurements and Derivative Instruments (Available-for-sale Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost	$ 186,735	$ 196,923
Gross unrealized gains	4
Gross unrealized losses	(35,014)	(38,944)
Estimated fair value	151,725	157,979
Government and related securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost	21,411	21,432
Gross unrealized gains	4
Gross unrealized losses	(5,937)	(5,688)
Estimated fair value	15,478	15,744
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost	50,170	50,367
Gross unrealized gains	0
Gross unrealized losses	(7,258)	(8,208)
Estimated fair value	42,912	42,159
Commingled fixed income securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost	1,847	1,835
Gross unrealized gains	0
Gross unrealized losses	(201)	(223)
Estimated fair value	1,646	1,612
Mortgage-backed / asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost	113,307	123,289
Gross unrealized gains	0
Gross unrealized losses	(21,618)	(24,825)
Estimated fair value	$ 91,689	$ 98,464