Stockholders' Equity and Stock-Based Compensation - Summary of Market-Based Shares Vesting Activity (Detail) - Market-Based Shares [Member] - Market-based [Member] $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($) shares
Vest Date March 14, 2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Date Vested	Mar. 14, 2018
Number of Shares Vested	141,599
Compensation Cost Recognized Upon Vesting \| $	$ 9.7
Shares withheld to satisfy tax withholding obligations	54,000
Vest Date March 23, 2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Date Vested	Mar. 23, 2018
Number of Shares Vested	141,481
Compensation Cost Recognized Upon Vesting \| $	$ 10.1
Shares withheld to satisfy tax withholding obligations	54,909

Date the equity-based payment instruments, excluding stock (or unit) options vest, in CCYY-MM-DD format.

No definition available.

Name:	payc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestDate
Namespace Prefix:	payc_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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

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

- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_AwardTypeAxis=payc_MarketBasedSharesAwardMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_VestingAxis=payc_MarketBasedVestingMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_AwardDateAxis=payc_VestDateMarchFourteenTwoThousandEighteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_AwardDateAxis=payc_VestDateMarchTwentyThreeTwoThousandEighteenMember
Namespace Prefix:
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