Convertible Senior Notes - Certain terms of the Notes (Details)	3 Months Ended
Mar. 31, 2021 USD ($) $ / shares
2027 Notes
Convertible Senior Notes
Interest Rate Per Year	1.25%
Fair value	$ 1,115,500,000
Conversion Rate Per $1,000 Principal Amount \| $ / shares	$ 0.00413
Remaining contractual life	6 years 2 months 12 days
2025 Notes
Convertible Senior Notes
Interest Rate Per Year	1.375%
Fair value	$ 750,000,000.0
Conversion Rate Per $1,000 Principal Amount \| $ / shares	$ 0.01866
Remaining contractual life	4 years 1 month 6 days
Livongo Notes
Convertible Senior Notes
Interest Rate Per Year	0.875%
Fair value	$ 906,600,000
Conversion Rate Per $1,000 Principal Amount \| $ / shares	$ 0.01394
Remaining contractual life	4 years 2 months 12 days
Notes
Convertible Senior Notes
Principal multiple amount used in the conversion of the debt instrument	$ 1,000

The remaining contractual life of the convertible debt instrument.

No definition available.

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- Definition

The principal multiple amount used in the conversion of the debt instrument.

+ References

No definition available.

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- Definition

The rate of interest that was being paid on the original debt issue that is being converted in the noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash 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=121583591&loc=d3e4332-108586

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-Section 50
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-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4304-108586

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- 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=120520924&loc=SL6031898-161870

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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- 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.

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