v3.5.0.2

Fair Value Measurements | 6 Months Ended
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Jun. 30, 2016
Fair Value Disclosures [Abstract] |
Fair Value Measurements | 4. FAIR VALUE MEASUREMENTS Accounting standards require that assets and liabilities carried at fair value will be classified and disclosed in one of the following three categories: Level 1: Quoted market prices in active markets for identical assets or liabilities. Level 2: Observable market based inputs or unobservable inputs that are corroborated by market data. Level 3: Unobservable inputs that are not corroborated by market data. The following table summarizes the valuation of our investments and financial instruments by the above pricing levels as of the valuation dates listed:
|  |  |  |  | June 30, 2016 |
|  | Total |  |  | (Level 1) |  |  | (Level 2) |
|  |  |  |  | (Thousands of dollars) |
Investments: |  |  |  |  |  |  |  |  |  |  |  |
Money market mutual funds |  | $ | 17,231 |  |  | $ | 17,231 |  |  | $ | — |
Commercial paper |  |  | 12,393 |  |  |  | — |  |  |  | 12,393 |
U.S. Government agencies |  |  | 28,312 |  |  |  | — |  |  |  | 28,312 |
Corporate bonds and notes |  |  | 244,322 |  |  |  | — |  |  |  | 244,322 |
|  |  | 302,258 |  |  |  | 17,231 |  |  |  | 285,027 |
Deferred compensation plan assets |  |  | 2,386 |  |  |  | 2,386 |  |  |  | — |
Total |  | $ | 304,644 |  |  | $ | 19,617 |  |  | $ | 285,027 |
|  |  |  |  | December 31, 2015 |
|  | Total |  |  | (Level 1) |  |  | (Level 2) |
Investments: |  |  |  |  |  |  |  |  |  |  |  |
Money market mutual funds |  | $ | 18,181 |  |  | $ | 18,181 |  |  | $ | — |
Commercial paper |  |  | 5,981 |  |  |  | — |  |  |  | 5,981 |
U.S. Government agencies |  |  | 11,469 |  |  |  | — |  |  |  | 11,469 |
Corporate bonds and notes |  |  | 264,228 |  |  |  | — |  |  |  | 264,228 |
|  |  | 299,859 |  |  |  | 18,181 |  |  |  | 281,678 |
Deferred compensation plan assets |  |  | 2,294 |  |  |  | 2,294 |  |  |  | — |
Total |  | $ | 302,153 |  |  | $ | 20,475 |  |  | $ | 281,678 |
We hold our short-term investments in an investment fund consisting of high quality money market instruments of governmental and private issuers, which is classified as a short-term investment. Level 1 inputs are quoted prices (unadjusted) for identical assets or liabilities in active markets. These items are traded with sufficient frequency and volume to provide pricing on an ongoing basis. The fair values of the shares of these funds are based on observable market prices, and therefore, have been categorized in Level 1 in the fair value hierarchy. Level 2 inputs reflect quoted prices for identical assets or liabilities that are not actively traded. These items may not be traded daily; examples include corporate bonds and U.S. government agencies debt. There have been no reclassifications of assets between Level 1 and Level 2 investments during the periods covered by the financial statements included in this report. We hold no Level 3 investments. Investments reflected on our balance sheets as Other assets, which we hold to fund liabilities under our Officers’ Deferred Compensation Plan, consist mainly of multiple investment funds that are highly liquid and diversified. Cash, accounts receivable, accounts payable and accrued liabilities, and our revolving credit facility debt all had fair values approximating their carrying amounts at June 30, 2016 and December 31, 2015. Our determination of the estimated fair value of our Senior Notes and our revolving credit facility debt is derived using Level 2 inputs, including quoted market indications of similar publicly-traded debt. The fair value of our Senior Notes, based on quoted market prices, was $463.8 million and $403.1 million at June 30, 2016 and December 31, 2015, respectively.

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- Definition The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 30 -URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13504-108611 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611 + Details
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