Borrowings - Schedule of Bank Line of Credit Advance, Junior Subordinated Debentures and Subordinated Debentures (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total	$ 411,000	$ 0
Junior subordinated debentures owed to unconsolidated subsidiary trusts	36,083	36,083
Subordinated debentures	48,988	48,893
First Defiance Statutory Trusts I [Member]
Debt Instrument [Line Items]
Junior subordinated debentures owed to unconsolidated subsidiary trusts	20,619	20,619
First Defiance Statutory Trusts II [Member]
Debt Instrument [Line Items]
Junior subordinated debentures owed to unconsolidated subsidiary trusts	15,464	15,464
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
Overnight Advances	411,000	0
Single maturity fixed rate advances	$ 0	$ 0

Overnight Advances

No definition available.

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- Definition

Single maturity fixed rate advances

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Subordinated debt and obligations.

+ References

No definition available.

+ Details

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

- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

+ Details

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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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- Definition

Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

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- Details

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