Leases - Schedule of Future Lease Payments under Operating Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Leases [Abstract]
Operating Leases, Lease Payments, 2020	$ 2,381
Operating Leases, Lease Payments, 2021	4,790
Operating Leases, Lease Payments, 2022	4,650
Operating Leases, Lease Payments, 2023	3,263
Operating Leases, Lease Payments, 2024	3,219
Operating Leases, Lease Payments, Thereafter	6,729
Operating Leases, Lease Payments, Total lease payments	25,032
Less: Imputed interest	(4,404)
Present value of lease liabilities	20,628
Less: Current portion of lease liabilities	(3,546)	$ (3,380)
Operating lease liabilities, net of current portion	17,082	$ 18,907
Operating Leases, Sublease Income, 2020	(697)
Operating Leases, Sublease Income, 2021	(1,414)
Operating Leases, Sublease Income, 2022	(1,457)
Operating Leases, Sublease Income, 2023	(123)
Operating Leases, Sublease Income, Total lease payments	(3,691)
Operating Leases, Net, 2020	1,684
Operating Leases, Net, 2021	3,376
Operating Leases, Net, 2022	3,193
Operating Leases, Net, 2023	3,140
Operating Leases, Net, 2024	3,219
Operating Leases, Net, Thereafter	6,729
Operating Leases, Net, Total lease payments	$ 21,341

Lessee operating lease liability payments due after year four.

No definition available.

Name:	pi_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lessee operating lease liability payments net of sublease income due.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseLiabilityPaymentsNetOfSubleaseIncomeDue
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessee operating lease liability payments net of sublease income due after year four.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseLiabilityPaymentsNetOfSubleaseIncomeDueAfterYearFour
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessee operating lease liability payments net of sublease income due year four.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseLiabilityPaymentsNetOfSubleaseIncomeDueYearFour
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessee operating lease liability payments net of sublease income due year one.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseLiabilityPaymentsNetOfSubleaseIncomeDueYearOne
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessee operating lease liability payments net of sublease income due year three.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseLiabilityPaymentsNetOfSubleaseIncomeDueYearThree
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessee operating lease liability payments net of sublease income due year two.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseLiabilityPaymentsNetOfSubleaseIncomeDueYearTwo
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessee operating lease liability payments net of sublease income remainder of fiscal year.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseLiabilityPaymentsNetOfSubleaseIncomeRemainderOfFiscalYear
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessee operating lease sublease income due.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseSubleaseIncomeDue
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessee operating lease sublease income due year one.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseSubleaseIncomeDueYearOne
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessee operating lease sublease income due year three.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseSubleaseIncomeDueYearThree
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessee operating lease sublease income due year two.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseSubleaseIncomeDueYearTwo
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lessee operating lease sublease income remainder of fiscal year.

+ References

No definition available.

+ Details

Name:	pi_LesseeOperatingLeaseSubleaseIncomeRemainderOfFiscalYear
Namespace Prefix:	pi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

+ Details

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

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

+ Details

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

- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

+ References

+ Details

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

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

+ Details

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

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

+ References

+ Details

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

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

+ References

+ Details

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