Fair Value Measurements (Fair Value Measurements On A Recurring Basis) (Details) - USD ($)
$ in Thousands |
Jun. 30, 2020 |
Dec. 31, 2019 |
Jun. 30, 2019 |
Dec. 31, 2018 |
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
|
| Cash equivalents, Carrying amount |
$ 2,262
|
$ 8,785
|
$ 1,025
|
$ 1,057
|
| Equity Securities, Fair Value |
6,790
|
45
|
|
|
| Commercial Paper [Member] |
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
|
| Cash equivalents, Carrying amount |
765
|
797
|
|
|
| Cash equivalents, Fair Value |
765
|
797
|
|
|
| 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 |
765
|
797
|
|
|
| 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 |
1,000
|
7,734
|
|
|
| Cash equivalents, Fair Value |
1,000
|
7,734
|
|
|
| Treasury bills, Carrying amount |
6,748
|
|
|
|
| Treasury bills, Fair Value |
6,748
|
|
|
|
| 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 |
1,000
|
7,734
|
|
|
| Treasury bills, Fair Value |
6,748
|
|
|
|
| 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
|
|
|
|
| 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
|
|
|
|
| Limited Marketable Company [Member] |
|
|
|
|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
|
|
|
|
| Equity Securities, Carrying amount |
42
|
45
|
|
|
| Equity Securities, Fair Value |
42
|
45
|
|
|
| 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 |
$ 42
|
$ 45
|
|
|