Fair Value Measurements (Fair Value Measurements On A Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents, Carrying amount	$ 7,646	$ 6,713
Treasury Bills, carrying value	1,980	3,000
Equity Securities, Fair Value	2,036	3,056
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, Carrying amount	56	56
Equity Securities, Fair Value	56	56
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, Fair Value	0	0
Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, Fair Value	0	0
Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, Fair Value	56	56
Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents, Carrying amount	1,377	1,520
Cash and cash equivalents, Fair Value	1,377	1,520
Commercial Paper [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents, Fair Value	1,377	1,520
Commercial Paper [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents, Fair Value	0	0
Commercial Paper [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents, Fair Value	0	0
Treasury Bills [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents, Carrying amount	5,974	5,000
Cash and cash equivalents, Fair Value	5,974	5,000
Treasury Bills, carrying value	1,980	3,000
Treasury Bills, fair value	1,980	3,000
Treasury Bills [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents, Fair Value	5,974	5,000
Treasury Bills, fair value	1,980	3,000
Treasury Bills [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents, Fair Value	0	0
Treasury Bills, fair value	0	0
Treasury Bills [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents, Fair Value	0	0
Treasury Bills, fair value	$ 0	$ 0