Investments (Details) - USD ($) |
3 Months Ended | ||
|---|---|---|---|
Mar. 31, 2019 |
Mar. 31, 2018 |
Dec. 31, 2018 |
|
| Investments, Debt and Equity Securities [Abstract] | |||
| Debt securities, trading | $ 1,405,000 | $ 1,308,000 | |
| Realized gain (loss) on trading securities | $ 100,000 | $ 0 | |
| X | ||||||||||
- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount of restricted investment in debt security measured at fair value with change in fair value recognized in net income (trading). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- References No definition available.
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