| Summary of Valuation of Investments and Financial Instruments Pricing Levels |
The following table summarizes the valuation of our investments and
financial instruments by the above pricing levels as of the
valuation dates listed:
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|
|
|
|
|
|
|
|
|
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| |
|
|
|
|
June 30, 2016 |
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| |
|
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 |
|
|
|
|
|
|
|
|
|
|
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