Investment Securities Table (Details) $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Debt Securities, Current	$ 9,591
Available-for-sale Securities, Debt Securities, Noncurrent	15,140
Available-for-sale Debt Securities, Amortized Cost Basis	24,731
Available-for-sale Debt Securities, Gross Unrealized Loss	102
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	9,575
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	15,054
Available-for-sale Securities, Debt Securities	24,629
Available-for-sale Debt Security Current [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	16
Available-for-sale Debt Security Noncurrent [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	$ 86

This item represents the cost of debt 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.

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