Available-For-Sale securities number of securities owned during period.

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- Definition

Available for sale Securities Number Of Securities Owned Unrealized Losses.

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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- Definition

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26853-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

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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.

+ References

No definition available.

+ Details

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Marketable Securities (Narrative) (Details) $ in Thousands	12 Months Ended
Marketable Securities (Narrative) (Details) $ in Thousands	Dec. 31, 2016 USD ($) Number	Dec. 31, 2014 USD ($)	Dec. 31, 2015 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities Number of Securities Owned \| Number	27
Available-For-Sale Securities Number Of Securities Owned Unrealized Losses \| Number	16
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	$ 10		$ 50
Available-for-sale Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	$ 100
Auction Rate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from Sale of Available-for-sale Securities, Total		$ 1,800
Available-for-sale Securities, Gross Realized Gain (Loss)		$ 600