v3.6.0.2

Financial Instruments (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 USD ($) position | Dec. 31, 2015 USD ($)
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract] |  |
Estimated Fair Value | $ 130,860 | $ 201,586
Realized gain | $ 200 | 0
Number of investments, unrealized loss position | position | 27 |
Interest income | $ 1,500 |
Amortized Cost |  |
Less than one year | 48,265 |
Greater than one year but less than five years | 83,320 |
Total | 131,585 |
Fair Value |  |
Less than one year | 48,212 |
Greater than one year but less than five years | 82,648 |
Total | 130,860 |
Available-for-sale securities |  |
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract] |  |
Cost | 142,362 | 208,968
Unrealized Gain |  | 3
Unrealized Loss | (725) | (1,419)
Estimated Fair Value | 141,637 | 207,552
Money market deposits |  |
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract] |  |
Cost | 10,777 | 5,966
Estimated Fair Value | 10,777 | 5,966
U.S. Treasury securities |  |
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract] |  |
Cost | 57,846 | 104,537
Unrealized Gain |  | 1
Unrealized Loss | (404) | (725)
Estimated Fair Value | 57,442 | 103,813
U.S. agency securities |  |
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract] |  |
Cost | 56,261 | 79,491
Unrealized Loss | (147) | (638)
Estimated Fair Value | 56,114 | 78,853
Municipal securities |  |
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract] |  |
Cost | 17,478 | 18,974
Unrealized Gain |  | 2
Unrealized Loss | (174) | (56)
Estimated Fair Value | 17,304 | 18,920
Cash equivalents | Available-for-sale securities |  |
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract] |  |
Estimated Fair Value | 10,777 | 5,966
Short-term investments | Available-for-sale securities |  |
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract] |  |
Estimated Fair Value | $ 130,860 | $ 201,586

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- Definition Amount before tax of unrealized gain 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 (b) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563 + 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 + Details
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- Definition Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth 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 -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62586-112803 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27198-111563 + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27198-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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