Fair Value Measurements and Derivative Instruments (Unrealized Holding Losses) (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Greater than 12 continuous months, Fair Value	$ 148,098	$ 157,979
Greater than 12 continuous months, Gross unrealized losses	29,964	38,944
Mutual funds
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Greater than 12 continuous months, Fair Value	1,715	1,612
Greater than 12 continuous months, Gross unrealized losses	171	223
Government securities
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Greater than 12 continuous months, Fair Value	13,486	15,744
Greater than 12 continuous months, Gross unrealized losses	5,557	5,688
Corporate debt securities
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Greater than 12 continuous months, Fair Value	43,895	42,159
Greater than 12 continuous months, Gross unrealized losses	5,586	8,208
Mortgage-backed securities
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Greater than 12 continuous months, Fair Value	89,002	90,628
Greater than 12 continuous months, Gross unrealized losses	18,650	24,313
Asset-backed securities
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Greater than 12 continuous months, Fair Value	0	7,836
Greater than 12 continuous months, Gross unrealized losses	$ 0	$ 512