Debt Instrument, Convertible, Associated Derivative Transactions, Number Of Shares1

No definition available.

Name:	dxcm_DebtInstrumentConvertibleAssociatedDerivativeTransactionsNumberOfShares
Namespace Prefix:	dxcm_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument Convertible Principal Amount Exercised

+ References

No definition available.

+ Details

Name:	dxcm_DebtInstrumentConvertiblePrincipalAmountExercised
Namespace Prefix:	dxcm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Debt Instrument, Convertible, Terms Of Conversion Feature, Conversion Amount

+ References

No definition available.

+ Details

Name:	dxcm_DebtInstrumentConvertibleTermsOfConversionFeatureConversionAmount
Namespace Prefix:	dxcm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Covenant Repurchase Price, Percentage

+ References

No definition available.

+ Details

Name:	dxcm_DebtInstrumentCovenantRepurchasePricePercentage
Namespace Prefix:	dxcm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Redemption Covenant, Percent Of Conversion Price, Last Reported Sale Price Of Common Stock

+ References

No definition available.

+ Details

Name:	dxcm_DebtInstrumentRedemptionCovenantPercentOfConversionPriceLastReportedSalePriceOfCommonStock
Namespace Prefix:	dxcm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Maximum Borrowing Capacity, Option to Increase, Amount

+ References

No definition available.

+ Details

Name:	dxcm_LineOfCreditFacilityMaximumBorrowingCapacityOptionToIncreaseAmount
Namespace Prefix:	dxcm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Maturity, Conditional Restrictions, Value of Unrestricted Cash on Hand Threshold

+ References

No definition available.

+ Details

Name:	dxcm_LineofCreditFacilityMaturityConditionalRestrictionsValueofUnrestrictedCashonHandThreshold
Namespace Prefix:	dxcm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Payments for Repurchase of Convertible Notes

+ References

No definition available.

+ Details

Name:	dxcm_PaymentsforRepurchaseofConvertibleNotes
Namespace Prefix:	dxcm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 25
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=123466103&loc=SL6014347-161799

+ Details

Name:	us-gaap_AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

+ Details

Name:	us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4332-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4304-108586

+ Details

Name:	us-gaap_DebtConversionConvertedInstrumentSharesIssued1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031898-161870

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

+ Details

Name:	us-gaap_DebtInstrumentConvertibleConversionPrice1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21521-112644

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21506-112644

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(5))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

+ Details

Name:	us-gaap_DebtInstrumentConvertibleConversionRatio1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69C
-URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69B
-URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

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

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

+ Details

Name:	us-gaap_DebtInstrumentRedemptionPricePercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of the liability for the conversion option reclassified to stockholders' equity when the embedded option no longer required separation from the host instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 15
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35708913&loc=d3e50896-113970

+ Details

Name:	us-gaap_EmbeddedDerivativeNoLongerBifurcatedAmountReclassifiedToStockholdersEquity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123467658&loc=d3e12355-112629

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123467658&loc=d3e12317-112629

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

+ Details

Name:	us-gaap_GainsLossesOnExtinguishmentOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromConvertibleDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfWarrants
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of shares issued during the period as a result of the conversion of convertible securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29-30)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1E
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21463-112644

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=dxcm_ConvertibleNotesDue2022Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=dxcm_ConvertibleNotesDue2023Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_HedgingDesignationAxis=us-gaap_DesignatedAsHedgingInstrumentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dxcm_DebtInstrumentConversionTermAxis=dxcm_DebtInstrumentConversionTermOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dxcm_DebtInstrumentConversionTermAxis=dxcm_DebtInstrumentConversionTermTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=dxcm_ConvertibleNotesDue2025Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_AdditionalPaidInCapitalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Debt - Narrative (Details)	1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended
Debt - Narrative (Details)	May 31, 2020 USD ($) $ / shares shares	Nov. 30, 2018 USD ($) d $ / shares shares	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($) shares	Jun. 30, 2021 USD ($) d	Jun. 30, 2020 USD ($) shares	Dec. 31, 2020 USD ($)	Dec. 31, 2018 USD ($)	Dec. 19, 2018 USD ($)	Jun. 30, 2017 USD ($)
Debt Instrument [Line Items]
Payments to repurchase convertible notes	$ 282,600,000				$ 0	$ 282,600,000
Repurchase and conversions of 2022 Notes (in shares) \| shares	1,953,067
Loss on extinguishment of debt			$ 0	$ 5,400,000	0	5,400,000
Proceeds from issuance of convertible notes, net of issuance costs					0	1,188,800,000
Equity component of 2025 Notes issuance, net of issuance costs				289,400,000		$ 289,400,000
Senior Notes
Debt Instrument [Line Items]
Principal amount			2,057,500,000		$ 2,057,500,000		$ 2,057,500,000
Senior Notes \| Senior Convertible Notes due 2022
Debt Instrument [Line Items]
Principal amount	$ 260,000,000.0									$ 400,000,000.0
Debt instrument convertible principal amount exercised				$ (102,800,000)
Interest rate on convertible notes (as a percent)										0.75%
Redemption price (as a percent)					100.00%
Senior Notes \| Senior Convertible Notes due 2023
Debt Instrument [Line Items]
Principal amount		$ 850,000,000.0	$ 850,000,000.0		$ 850,000,000.0		850,000,000.0
Interest rate on convertible notes (as a percent)		0.75%
Proceeds from issuance of convertible notes, net of issuance costs		$ 836,600,000
Conversion ratio		0.0060869
Conversion amount		$ 1,000
Conversion price of convertible notes (USD per share) \| $ / shares		$ 164.29
Holder's repurchase price percentage in event of fundamental change (as a percent)			100.00%		100.00%
Number of trading days \| d		60
Proportion of conversion price (as a percent)					130.00%
Redemption price (as a percent)					100.00%
Stock counterparties to acquire with warrants purchased (shares) \| shares		5,200,000
Proceeds from sale of warrants		$ 183,800,000
Exercise price of warrants or rights (USD per share) \| $ / shares		$ 198.38
Senior Notes \| Senior Convertible Notes due 2023 \| Designated as Hedging Instrument
Debt Instrument [Line Items]
Stock issued upon conversion of senior notes (in shares) \| shares		5,200,000
Equity component of 2025 Notes issuance, net of issuance costs		$ 218,900,000
Senior Notes \| Senior Convertible Notes due 2023 \| Debt Instrument Conversion Term One \| Minimum
Debt Instrument [Line Items]
Number of trading days \| d					20
Proportion of applicable conversion price (as a percent)					130.00%
Senior Notes \| Senior Convertible Notes due 2023 \| Debt Instrument Conversion Term One \| Maximum
Debt Instrument [Line Items]
Number of trading days \| d					30
Senior Notes \| Senior Convertible Notes due 2023 \| Debt Instrument Conversion Term Two
Debt Instrument [Line Items]
Number of trading days \| d					5
Senior Notes \| Senior Convertible Notes due 2023 \| Debt Instrument Conversion Term Two \| Maximum
Debt Instrument [Line Items]
Number of trading days \| d					5
Proportion of applicable conversion price (as a percent)					98.00%
Senior Notes \| Senior Convertible Notes due 2025
Debt Instrument [Line Items]
Principal amount	$ 1,210,000,000		$ 1,207,500,000		$ 1,207,500,000		1,207,500,000
Interest rate on convertible notes (as a percent)	0.25%
Proceeds from issuance of convertible notes, net of issuance costs	$ 1,190,000,000
Conversion ratio	0.0016655
Conversion price of convertible notes (USD per share) \| $ / shares	$ 600.42
Holder's repurchase price percentage in event of fundamental change (as a percent)			100.00%		100.00%
Proportion of conversion price (as a percent)					130.00%
Senior Notes \| Senior Convertible Notes due 2025 \| Designated as Hedging Instrument
Debt Instrument [Line Items]
Recognized additional paid-in capital from cash conversion option							$ 289,400,000
Senior Notes \| Senior Convertible Notes due 2025 \| Maximum
Debt Instrument [Line Items]
Conversion ratio	0.0023732
Senior Notes \| Senior Convertible Notes due 2025 \| Debt Instrument Conversion Term One \| Minimum
Debt Instrument [Line Items]
Number of trading days \| d					20
Proportion of applicable conversion price (as a percent)					130.00%
Senior Notes \| Senior Convertible Notes due 2025 \| Debt Instrument Conversion Term One \| Maximum
Debt Instrument [Line Items]
Number of trading days \| d					30
Senior Notes \| Senior Convertible Notes due 2025 \| Debt Instrument Conversion Term Two
Debt Instrument [Line Items]
Number of trading days \| d					5
Senior Notes \| Senior Convertible Notes due 2025 \| Debt Instrument Conversion Term Two \| Maximum
Debt Instrument [Line Items]
Number of trading days \| d					5
Proportion of applicable conversion price (as a percent)					98.00%
Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity of revolving credit agreement			$ 200,000,000.0		$ 200,000,000.0				$ 200,000,000.0
Option to increase revolving line of credit									$ 500,000,000.0
Value of unrestricted cash on hand threshold					$ 100,000,000.0
Line of Credit \| Minimum
Debt Instrument [Line Items]
Interest rate on convertible notes (as a percent)			0.375%		0.375%
Unused capacity fee (as a percent)					0.20%
Line of Credit \| Minimum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)					1.375%
Line of Credit \| Maximum
Debt Instrument [Line Items]
Interest rate on convertible notes (as a percent)			1.00%		1.00%
Unused capacity fee (as a percent)					0.30%
Line of Credit \| Maximum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)					2.00%
Common Stock
Debt Instrument [Line Items]
Repurchase and conversions of 2022 Notes (in shares) \| shares				3,000,000.0		3,000,000.0
Common Stock \| Senior Notes \| Senior Convertible Notes due 2022
Debt Instrument [Line Items]
Repurchase and conversions of 2022 Notes (in shares) \| shares				1,037,319
Additional Paid-In Capital
Debt Instrument [Line Items]
Equity component of 2025 Notes issuance, net of issuance costs				$ 289,400,000		$ 289,400,000
Additional Paid-In Capital \| Senior Notes \| Senior Convertible Notes due 2023
Debt Instrument [Line Items]
Recognized additional paid-in capital from cash conversion option								$ 171,600,000