Cash paid for paycheck protection program.

No definition available.

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Namespace Prefix:	pfc_
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Period Type:	duration

- Definition

Paycheck Protection Program loans.

+ References

No definition available.

+ Details

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

- Definition

Specific reserves for customers whose loan terms have been modified in troubled debt restructurings as of balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	pfc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of increase (decrease) in allowance for credit loss on financing receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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Balance Type:	debit
Period Type:	instant

- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
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Balance Type:	debit
Period Type:	duration

- Definition

Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of undisbursed portion of the loan receivable balance (loans in process). Excludes loans and leases covered under loss sharing agreements.

+ References

No definition available.

+ Details

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

- Definition

Amount of expense related to estimated loss from loan and lease transactions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 230
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-Section 45
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Balance Type:	debit
Period Type:	duration

- Definition

Unused amount of commitments to extend credit to customers.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Details

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- Details

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- Details

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Loans - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
Loans - Additional Information (Details) - USD ($)	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Cash paid for paycheck protection program			$ 636,900,000
Anticipated credit losses	$ 3,706,000	$ 1,594,000	9,483,000	$ (9,549,000)
Loans and Leases Receivable, Loans in Process	724,797,000		724,797,000		$ 477,890,000
Scenario Plan [Member]
Anticipated credit losses			7,100,000
Subsequently Defaulted [Member]
Financing Receivable, Allowance for Credit Losses, Period Increase (decrease)				0
TDRs [Member]
Financing Receivable, Modifications, Recorded Investment	19,800		19,800		11,900,000
Specified Reserves, Provision for Troubled Debt Restructurings	353,000,000		353,000,000		378,000,000
Loans and Leases Receivable, Impaired, Commitment to Lend	319,000,000		319,000,000		348,000,000
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down			12,900
Financing Receivable, Allowance for Credit Losses, Period Increase (decrease)	28,000,000	$ 9,000,000	428,000,000	$ 382,000,000
TDRs [Member] \| Subsequently Defaulted [Member]
Financing Receivable, Allowance for Credit Losses, Period Increase (decrease)	9,000,000		11,000,000
Consumer Portfolio Segment [Member]
Loans and Leases Receivable, Loans in Process	2,700,000		2,700,000		3,300,000
Other Loans [Member] \| Commercial [Member]
PPP loans	1,200,000		1,200,000		$ 58,900,000
Unfunded Loan Commitments [Member]
Unfunded loan commitments	$ 1,800,000,000		$ 1,800,000,000