Conversion Of Notes Base Conversion Price

No definition available.

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- Definition

Debt Instrument, Convertible, Threshold Percentage of Notes Price Trigger

+ References

No definition available.

+ Details

Name:	now_DebtInstrumentConvertibleThresholdPercentageOfNotesPriceTrigger
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Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Percentage Of Purchase Price Of Notes Which Should Be Paid Upon Fundamental Change

+ References

No definition available.

+ Details

Name:	now_PercentageOfPurchasePriceOfNotesWhichShouldBePaidUponFundamentalChange
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Period Type:	duration

- Definition

Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

+ Details

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instruments must exceed threshold percentage for a specified number of trading days to trigger conversion feature, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays
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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:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdTradingDays
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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
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Data Type:	num: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

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- Details

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- Details

Name:	us-gaap_DebtConversionByUniqueDescriptionAxis=now_NotesPriceTriggerMeasurementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=now_A2022ConvertibleSeniorNotesMember
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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=now_A2018ConvertibleSeniorNotesMember
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Period Type:

Convertible Senior Notes - Additional Information (Details)	6 Months Ended
	Jun. 30, 2017 USD ($) day	Dec. 31, 2016 USD ($)	Nov. 30, 2013 USD ($)
Debt Instrument [Line Items]
Percentage of purchase price of Notes which should be paid upon fundamental change	100.00%
Stock Price Trigger Measurement [Member]
Debt Instrument [Line Items]
Trading days threshold \| day	20
Consecutive trading days threshold, total	30 days
Threshold percentage of stock price trigger	130.00%
Notes Price Trigger Measurement [Member]
Debt Instrument [Line Items]
Trading days threshold \| day	5
Consecutive trading days threshold, total	5 days
Conversion of notes base conversion price	$ 1,000
Threshold percentage of notes price trigger	98.00%
2022 Notes
Debt Instrument [Line Items]
Face amount of debt	$ 782,500,000	$ 0
Stated interest rate	0.00%
Remaining discount amortization period	59 months
2018 Notes
Debt Instrument [Line Items]
Face amount of debt	$ 575,000,000	$ 575,000,000	$ 575,000,000.0
Stated interest rate			0.00%
Remaining discount amortization period	16 months