Fair Value Measurements (Fair Value Measurements On A Recurring Basis) (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, Carrying amount	$ 6,429	$ 6,713
Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, Carrying amount	1,141	1,520
Cash equivalents, Fair Value	1,141	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 equivalents, Fair Value	1,141	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 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 equivalents, Fair Value	0	0
Treasury Bills [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, Carrying amount	4,993	5,000
Cash equivalents, Fair Value	4,993	5,000
Treasury bills, Carrying amount	2,996	3,000
Treasury bills, Fair Value	2,996	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 equivalents, Fair Value	4,993	5,000
Treasury bills, Fair Value	2,996	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 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 equivalents, Fair Value	0	0
Treasury bills, Fair Value	0	0
Limited Marketable Company [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
Limited Marketable Company [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
Limited Marketable Company [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
Limited Marketable Company [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