XML 95 R47.htm IDEA: XBRL DOCUMENT v3.20.4

FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - Fair Value Measurements on a Recurring Basis (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Investments	$ 451	$ 342
Total	2,094	1,798
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Total		1
Fair Value Measurements on a Recurring Basis
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	13	92
Investments	195	194
Restricted cash equivalents	99	70
Restricted investments	256	148
Total	563	504
Fair Value Measurements on a Recurring Basis | Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Investments	24	30
Fair Value Measurements on a Recurring Basis | Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Investments	93	96
Restricted investments	35	28
Fair Value Measurements on a Recurring Basis | U.S. government agencies and government-sponsored agencies
Debt Securities, Available-for-sale [Line Items]
Investments	5	5
Restricted investments	23	9
Fair Value Measurements on a Recurring Basis | U.S. treasuries
Debt Securities, Available-for-sale [Line Items]
Investments	67	53
Restricted investments	198	110
Fair Value Measurements on a Recurring Basis | Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Restricted investments		1
Fair Value Measurements on a Recurring Basis | Other debt securities
Debt Securities, Available-for-sale [Line Items]
Investments	6	10
Fair Value Measurements on a Recurring Basis | Level 1
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	2	89
Investments	0	0
Restricted cash equivalents	99	56
Restricted investments	0	0
Total	101	145
Fair Value Measurements on a Recurring Basis | Level 1 | Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Investments	0	0
Fair Value Measurements on a Recurring Basis | Level 1 | Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Investments	0	0
Restricted investments	0	0
Fair Value Measurements on a Recurring Basis | Level 1 | U.S. government agencies and government-sponsored agencies
Debt Securities, Available-for-sale [Line Items]
Investments	0	0
Restricted investments	0	0
Fair Value Measurements on a Recurring Basis | Level 1 | U.S. treasuries
Debt Securities, Available-for-sale [Line Items]
Investments	0	0
Restricted investments	0	0
Fair Value Measurements on a Recurring Basis | Level 1 | Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Restricted investments		0
Fair Value Measurements on a Recurring Basis | Level 1 | Other debt securities
Debt Securities, Available-for-sale [Line Items]
Investments	0	0
Fair Value Measurements on a Recurring Basis | Level 2
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	11	3
Investments	195	194
Restricted cash equivalents	0	14
Restricted investments	256	148
Total	462	359
Fair Value Measurements on a Recurring Basis | Level 2 | Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Investments	24	30
Fair Value Measurements on a Recurring Basis | Level 2 | Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Investments	93	96
Restricted investments	35	28
Fair Value Measurements on a Recurring Basis | Level 2 | U.S. government agencies and government-sponsored agencies
Debt Securities, Available-for-sale [Line Items]
Investments	5	5
Restricted investments	23	9
Fair Value Measurements on a Recurring Basis | Level 2 | U.S. treasuries
Debt Securities, Available-for-sale [Line Items]
Investments	67	53
Restricted investments	198	110
Fair Value Measurements on a Recurring Basis | Level 2 | Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Restricted investments		1
Fair Value Measurements on a Recurring Basis | Level 2 | Other debt securities
Debt Securities, Available-for-sale [Line Items]
Investments	6	10
Money market mutual funds | Fair Value Measurements on a Recurring Basis
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	2	89
Money market mutual funds | Fair Value Measurements on a Recurring Basis | Level 1
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	2	89
Money market mutual funds | Fair Value Measurements on a Recurring Basis | Level 2
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	0	0
U.S. treasuries | Fair Value Measurements on a Recurring Basis
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	11	3
U.S. treasuries | Fair Value Measurements on a Recurring Basis | Level 1
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	0	0
U.S. treasuries | Fair Value Measurements on a Recurring Basis | Level 2
Debt Securities, Available-for-sale [Line Items]
Cash equivalents	$ 11	$ 3

X

- Definition

Amount of 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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesDebtSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_CashEquivalentsAtCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Cash and investments whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

+ References

No definition available.

+ Details

Name:	us-gaap_RestrictedCashAndInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of cash equivalents restricted as to withdrawal or usage. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(2))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=121583591&loc=SL98516268-108586

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(1)(a))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

Name:	us-gaap_RestrictedCashEquivalents
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The aggregate value of all restricted investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-12.6(c))
-URI http://asc.fasb.org/extlink&oid=120401592&loc=d3e611133-123010

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-12B(Footnote 11(c)))
-URI http://asc.fasb.org/extlink&oid=120401592&loc=d3e611197-123010

+ Details

Name:	us-gaap_RestrictedInvestmentsAtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_CertificatesOfDepositMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_OtherDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CashAndCashEquivalentsAxis=us-gaap_MoneyMarketFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CashAndCashEquivalentsAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: