XML 43 R29.htm IDEA: XBRL DOCUMENT
v3.19.1

SHORT-TERM AND LONG-TERM INVESTMENTS (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract] |
Summary of Amortized Costs, Gross Unrealized Gains and Losses and Estimated Fair Values of Available-For-Sale Marketable Securities | The following table summarizes amortized costs, gross unrealized gains and losses and estimated fair values of available-for-sale marketable securities as of December 31, 2018 and 2017:
|  | Amortized cost |  |  | Gross unrealized gains |  |  | Gross unrealized losses |  |  | Estimated fair value (Level 2 within the fair value hierarchy) |
|  | December 31, |  |  | December 31, |  |  | December 31, |  |  | December 31, |
|  | 2018 |  |  | 2017 |  |  | 2018 |  |  | 2017 |  |  | 2018 |  |  | 2017 |  |  | 2018 |  |  | 2017 |
Corporate debentures |  | $ | 457,943 |  |  | $ | 189,836 |  |  | $ | 190 |  |  | $ | 9 |  |  | $ | 1,993 |  |  | $ | 908 |  |  | $ | 456,141 |  |  | $ | 188,937 |
U.S. Treasuries |  |  | 21,944 |  |  |  | 7,007 |  |  |  | - |  |  |  | - |  |  |  | 226 |  |  |  | 170 |  |  |  | 21,717 |  |  |  | 6,837 |
U.S. Government Agencies |  |  | 10,854 |  |  |  | 998 |  |  |  | 16 |  |  |  | - |  |  |  | 1 |  |  |  | 1 |  |  |  | 10,869 |  |  |  | 997 |
|  | $ | 490,741 |  |  | $ | 197,841 |  |  | $ | 206 |  |  | $ | 9 |  |  | $ | 2,220 |  |  | $ | 1,079 |  |  | $ | 488,727 |  |  | $ | 196,771 |
Scheduled Maturities of Available-for-Sale Marketable Securities | The scheduled maturities of available-for-sale marketable securities as of December 31, 2018 are as follows:
|  | Amortized |  |  | Estimated |
|  | cost |  |  | fair value |
Due within one year |  | $ | 244,233 |  |  | $ | 243,729 |
Due after one year through five years |  |  | 246,508 |  |  |  | 244,998 |
|  | $ | 490,741 |  |  | $ | 488,727 |
Schedule of Unrealized Losses and Fair Values | Investments with continuous unrealized losses for less than 12 months and 12 months or greater and their related fair values as of December 31, 2018 and 2017 are as indicated in the following tables:
|  | December 31, 2018 |
|  | Investments with continuous unrealized losses for less than 12 months |  |  | Investments with continuous unrealized losses for 12 months or greater |  |  | Total Investments with continuous unrealized losses |
|  | Fair value |  |  | Unrealized losses |  |  | Fair value |  |  | Unrealized losses |  |  | Fair value |  |  | Unrealized losses |
Corporate debentures |  | $ | 231,845 |  |  | $ | (754 | ) |  | $ | 113,870 |  |  | $ | (1,239 | ) |  | $ | 345,715 |  |  | $ | (1,993 | )
U.S. treasuries |  |  | 14,926 |  |  |  | (12 | ) |  |  | 6,791 |  |  |  | (214 | ) |  |  | 21,717 |  |  |  | (226 | )
U.S. Government agencies |  |  | 7,932 |  |  |  | (1 | ) |  |  | - |  |  |  | - |  |  |  | 7,932 |  |  |  | (1 | )
|  | $ | 254,703 |  |  | $ | (767 | ) |  | $ | 120,661 |  |  | $ | (1,453 | ) |  | $ | 375,364 |  |  | $ | (2,220 | )
|  | December 31, 2017 |
|  | Investments with continuous unrealized losses for less than 12 months |  |  | Investments with continuous unrealized losses for 12 months or greater |  |  | Total Investments with continuous unrealized losses |
|  | Fair value |  |  | Unrealized losses |  |  | Fair value |  |  | Unrealized losses |  |  | Fair value |  |  | Unrealized losses |
Corporate debentures |  | $ | 135,252 |  |  | $ | (711 | ) |  | $ | 49,076 |  |  | $ | (198 | ) |  | $ | 184,328 |  |  | $ | (909 | )
U.S. treasuries |  |  | - |  |  |  | - |  |  |  | 6,837 |  |  |  | (170 | ) |  |  | 6,837 |  |  |  | (170 | )
U.S. Government agencies |  |  | 997 |  |  |  | - |  |  |  | - |  |  |  | - |  |  |  | 997 |  |  |  | - |
|  | $ | 136,249 |  |  | $ | (711 | ) |  | $ | 55,913 |  |  | $ | (368 | ) |  | $ | 192,162 |  |  | $ | (1,079 | )

X
- Definition Tabular disclosure of maturities of an entity's investments as well as any other information pertinent to the investments. + References No definition available. + Details
Name: | us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the reconciliation of available-for-sale securities from cost basis to fair value. + References No definition available. + Details
Name: | us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition For all investments in an unrealized loss position, including those for which other-than-temporary impairments have not been recognized in earnings (including investments for which a portion of an other-than-temporary impairment has been recognized in other comprehensive income), a tabular disclosure of the aggregate related fair value of investments with unrealized losses and the aggregate amount of unrealized losses (that is, the amount by which amortized cost basis exceeds fair value). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
Name: | us-gaap_ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration