v3.3.1.900

Fair Value Measurements and Disclosures (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Fair value adjustment of marketable securities and deferred compensation plan liability |  |  |  |
Net gain on marketable securities |  | $ (269) | $ 397 | $ 1,489
Fair Value (Level 1) [Member] |  |  |  |
Assets and Liabilities Reported at Fair Value |  |  |  |
Marketable securities | [1],[2] | $ 12,882 | $ 11,971 |
[1] | Fair value calculated using Level 1 inputs based on quoted prices in active markets for identical securities.
[2] | The marketable securities are held in a limited rabbi trust.

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- Definition This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. + References No definition available. + Details
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- Definition This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Article 5 + Details
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