Marketable Investments - Unrealized Losses on Debt Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Less than 12 Months - Market Value	$ 13,098	$ 11,604
Less than 12 Month - Unrealized Losses	8	153
12 Months or Greater - Market Value	6,872	8,084
12 Months or Greater - Unrealized Losses	71	66
Corporate Obligations [Member]
Debt Securities, Available-for-Sale [Line Items]
Less than 12 Months - Market Value	13,098	9,619
Less than 12 Month - Unrealized Losses	8	139
12 Months or Greater - Market Value	4,879	8,084
12 Months or Greater - Unrealized Losses	64	66
Federal Agency Obligations [Member]
Debt Securities, Available-for-Sale [Line Items]
Less than 12 Months - Market Value	0	1,985
Less than 12 Month - Unrealized Losses	0	14
12 Months or Greater - Market Value	1,993	0
12 Months or Greater - Unrealized Losses	$ 7	$ 0