v3.19.3.a.u2

Financial Instruments - Summary of Cash and Available-for-Sale Securities by Significant Investment Category (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 1,024,106 | $ 1,037,372
Level 2 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 1,259,980 | 1,695,737
Unrealized Gains | 3,047 | 120
Unrealized Losses | (40) | (1,440)
Fair Value | 1,262,987 | 1,694,417
Level 2 | Cash and Cash Equivalents |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 235,876 | 658,364
Level 2 | Current Marketable Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 867,124 | 863,063
Level 2 | Non- Current Marketable Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 159,987 | 172,990
Cash and Cash Equivalents |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 225,874 | 658,365
Unrealized Gains | 0 | 20
Unrealized Losses | 0 | (21)
Fair Value | 225,874 | 658,364
Cash and Cash Equivalents | Cash and Cash Equivalents |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 225,874 | 658,364
Cash and Cash Equivalents | Current Marketable Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 0 | 0
Cash and Cash Equivalents | Non- Current Marketable Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 0 | 0
Certificates of deposit | Level 2 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 82,028 | 173,102
Unrealized Gains | 79 | 42
Unrealized Losses | (6) | (36)
Fair Value | 82,101 | 173,108
Certificates of deposit | Level 2 | Cash and Cash Equivalents |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 10,002 | 0
Certificates of deposit | Level 2 | Current Marketable Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 69,197 | 157,920
Certificates of deposit | Level 2 | Non- Current Marketable Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 2,902 | 15,188
U.S. treasury securities | Level 2 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 117,891 | 152,205
Unrealized Gains | 260 | 18
Unrealized Losses | (2) | (48)
Fair Value | 118,149 | 152,175
U.S. treasury securities | Level 2 | Cash and Cash Equivalents |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 0 | 0
U.S. treasury securities | Level 2 | Current Marketable Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 110,186 | 152,175
U.S. treasury securities | Level 2 | Non- Current Marketable Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 7,963 | 0
Debt securities of U.S. government agencies and corporate entities | Level 2 |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 834,187 | 712,065
Unrealized Gains | 2,708 | 40
Unrealized Losses | (32) | (1,335)
Fair Value | 836,863 | 710,770
Debt securities of U.S. government agencies and corporate entities | Level 2 | Cash and Cash Equivalents |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 0 | 0
Debt securities of U.S. government agencies and corporate entities | Level 2 | Current Marketable Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | 687,741 | 552,968
Debt securities of U.S. government agencies and corporate entities | Level 2 | Non- Current Marketable Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Fair Value | $ 149,122 | $ 157,802

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 + Details
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