Investments - Amortized Cost and Estimated Fair Values of AFS Securities (Details) - USD ($) |
Sep. 30, 2017 |
Dec. 31, 2016 |
|---|---|---|
| Schedule of Available-for-sale Securities [Line Items] | ||
| Amortized Cost | $ 1,799,000 | |
| Gross Unrealized Gains | 0 | |
| Gross Unrealized Losses | (23,000) | |
| Fair Value | 1,776,000 | |
| U.S. government security funds | ||
| Schedule of Available-for-sale Securities [Line Items] | ||
| Amortized Cost | 1,799,000 | |
| Gross Unrealized Gains | 0 | |
| Gross Unrealized Losses | $ 0 | (23,000) |
| Fair Value | $ 1,776,000 |
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Details
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