Investments (Amortized cost and Fair Value of Marketable Securities) (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Balance Sheet Related Disclosures [Abstract]
Due in less than 1 year, Amortized Cost	$ 23,271
Due within 1-2 years, Amortized Cost	13,529
Total, Amortized Cost	36,800
Due in less than 1 year, Fair Value	23,249
Due within 1-2 years, Fair Value	13,483
Total, Fair Value	$ 36,732

Available-for-sale Securities, Debt Maturities, Year One Through Two, Amortized Cost Basis

No definition available.

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- Definition

Available-for-sale Securities, Debt Maturities, Year One Through Two, Fair Value

+ References

No definition available.

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- Definition

Fair value of investment in available-for-sale debt securities with a single maturity date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27198-111563

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Amount of investment in available-for-sale debt securities with a single maturity date at cost, after adjustments, including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in the statement of income and fair value hedge accounting adjustments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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-Subparagraph (d)
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- Definition

Amount after adjustments of available-for-sale debt securities at cost, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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