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Cash Equivalents And Restricted Securities (Tables) | 3 Months Ended
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Mar. 31, 2018
Cash Equivalents And Restricted Securities [Abstract] |
Summary Of Cash Equivalents And Restricted Securities |
﻿ |  |  |  |  |  |  |  |
﻿ |  |  |  | Unrealized |  | Estimated
﻿ |  |  |  | Holding |  | Market
﻿March 31, 2018 | Cost Basis |  | Gains |  | Value
﻿Cash equivalents: |  |  |  |  |  |  |  |
﻿Money market funds | $ | 373 |  | $ | -- |  | $ | 373
﻿Restricted securities: |  |  |  |  |  |  |  |
﻿Money market funds |  | 808 |  |  | -- |  |  | 808
﻿ |  |  |  |  |  |  |  |
﻿ |  |  |  | Unrealized |  | Estimated
﻿ |  |  |  | Holding |  | Market
﻿December 31, 2017 | Cost Basis |  | Gains |  | Value
﻿Cash equivalents: |  |  |  |  |  |  |  |
﻿Money market funds | $ | 372 |  | $ | -- |  | $ | 372
﻿Restricted securities: |  |  |  |  |  |  |  |
﻿Money market funds |  | 776 |  |  | -- |  |  | 776
﻿

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- References No definition available. + Details
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- Definition Tabular disclosure of the components of cash, cash equivalents, and investments. + References No definition available. + Details
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