Fair Value Measurements - Schedule of Financial Instruments, Carrying and Fair Values (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	$ 976,919	$ 1,063,079
Investment securities held to maturity	453,629	479,425
FHLBNY stock	57,298	68,813
Equity securities, at fair value	825	635
Loans, net of allowance for loan losses	7,277,360	7,195,026
Certificates of deposit	734,027	750,492
Total deposits	7,102,609	6,830,122
Borrowings	1,125,146	1,442,282
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
FHLBNY stock		68,813
Equity securities, at fair value	825
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
FHLBNY stock		0
Equity securities, at fair value	0
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
FHLBNY stock		0
Equity securities, at fair value	0
Mortgage-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	947,430	1,034,969
Investment securities held to maturity	118	187
State and municipal obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	4,079	2,912
Investment securities held to maturity	437,074	463,801
Corporate obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	25,410	25,198
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	186,748	142,661
Available for sale debt securities, at fair value	976,919	1,063,079
Investment securities held to maturity	453,629	479,425
FHLBNY stock	57,298	68,813
Equity securities, at fair value	825	635
Loans, net of allowance for loan losses	7,277,360	7,195,026
Derivative assets	39,305	15,634
Deposits other than certificates of deposits	6,368,582	6,079,630
Certificates of deposit	734,027	750,492
Total deposits	7,102,609	6,830,122
Borrowings	1,125,146	1,442,282
Derivative liabilities	39,356	14,766
Carrying Value \| Agency obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value		0
Investment securities held to maturity	6,599	4,989
Carrying Value \| Mortgage-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	947,430	1,034,969
Investment securities held to maturity	118	187
Carrying Value \| State and municipal obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	4,079	2,912
Investment securities held to maturity	437,074	463,801
Carrying Value \| Corporate obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	25,410	25,198
Investment securities held to maturity	9,838	10,448
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	186,748	142,661
Available for sale debt securities, at fair value	976,919	1,063,079
Investment securities held to maturity	467,966	479,740
FHLBNY stock	57,298	68,813
Equity securities, at fair value	825	635
Loans, net of allowance for loan losses	7,296,744	7,104,380
Derivative assets	39,305	15,634
Deposits other than certificates of deposits	6,368,582	6,079,630
Certificates of deposit	734,047	746,753
Total deposits	7,102,629	6,826,383
Borrowings	1,127,569	1,431,001
Derivative liabilities	39,356	14,766
Fair Value \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	186,748	142,661
Available for sale debt securities, at fair value	0	0
Investment securities held to maturity	6,601	4,896
FHLBNY stock	57,298
Equity securities, at fair value		635
Loans, net of allowance for loan losses	0	0
Derivative assets	0	0
Deposits other than certificates of deposits	6,368,582	6,079,630
Certificates of deposit	0	0
Total deposits	6,368,582	6,079,630
Borrowings	0	0
Derivative liabilities	0	0
Fair Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	0	0
Available for sale debt securities, at fair value	976,919	1,063,079
Investment securities held to maturity	461,365	474,844
FHLBNY stock	0
Equity securities, at fair value		0
Loans, net of allowance for loan losses	0	0
Derivative assets	39,305	15,634
Deposits other than certificates of deposits	0	0
Certificates of deposit	734,047	746,753
Total deposits	734,047	746,753
Borrowings	1,127,569	1,431,001
Derivative liabilities	39,356	14,766
Fair Value \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	0	0
Available for sale debt securities, at fair value	0	0
Investment securities held to maturity	0	0
FHLBNY stock	0
Equity securities, at fair value		0
Loans, net of allowance for loan losses	7,296,744	7,104,380
Derivative assets	0	0
Deposits other than certificates of deposits	0	0
Certificates of deposit	0	0
Total deposits	0	0
Borrowings	0	0
Derivative liabilities	0	0
Fair Value \| Agency obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value		0
Investment securities held to maturity	6,601	4,896
Fair Value \| Agency obligations \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value		0
Investment securities held to maturity	6,601	4,896
Fair Value \| Agency obligations \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value		0
Investment securities held to maturity	0	0
Fair Value \| Agency obligations \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value		0
Investment securities held to maturity	0	0
Fair Value \| Mortgage-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	947,430	1,034,969
Investment securities held to maturity	122	190
Fair Value \| Mortgage-backed securities \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	0	0
Investment securities held to maturity	0	0
Fair Value \| Mortgage-backed securities \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	947,430	1,034,969
Investment securities held to maturity	122	190
Fair Value \| Mortgage-backed securities \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	0	0
Investment securities held to maturity	0	0
Fair Value \| State and municipal obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	4,079	2,912
Investment securities held to maturity	451,353	464,363
Fair Value \| State and municipal obligations \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	0	0
Investment securities held to maturity	0	0
Fair Value \| State and municipal obligations \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	4,079	2,912
Investment securities held to maturity	451,353	464,363
Fair Value \| State and municipal obligations \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	0	0
Investment securities held to maturity	0	0
Fair Value \| Corporate obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	25,410	25,198
Investment securities held to maturity	9,890	10,291
Fair Value \| Corporate obligations \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	0	0
Investment securities held to maturity	0	0
Fair Value \| Corporate obligations \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	25,410	25,198
Investment securities held to maturity	9,890	10,291
Fair Value \| Corporate obligations \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale debt securities, at fair value	0	0
Investment securities held to maturity	$ 0	$ 0

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesDebtSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3044-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118951113&loc=d3e6676-107765

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_CashAndCashEquivalentsAtCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

+ Details

Name:	us-gaap_DerivativeAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

+ Details

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

- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

+ Details

Name:	us-gaap_EquitySecuritiesFvNi
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

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

- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809

+ Details

Name:	us-gaap_FederalHomeLoanBankStock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

+ Details

Name:	us-gaap_HeldToMaturitySecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of interest-bearing domestic certificate of deposit liabilities.

+ References

+ Details

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

- Definition

Amount of interest-bearing domestic deposit liabilities classified as other. Excludes certificates of deposit.

+ References

+ Details

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

- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

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 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_LoansAndLeasesReceivableNetReportedAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_MortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=pfs_StateAndMunicipalObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByMeasurementBasisAxis=us-gaap_CarryingReportedAmountFairValueDisclosureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByMeasurementBasisAxis=us-gaap_EstimateOfFairValueFairValueDisclosureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: