Basis of Presentation (Policies)	3 Months Ended
Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	The consolidated financial statements include the accounts of Penns Woods Bancorp, Inc. (the “Company”) and its wholly-owned subsidiaries: Woods Investment Company, Inc., Woods Real Estate Development Company, Inc., Luzerne Bank, and Jersey Shore State Bank (Jersey Shore State Bank and Luzerne Bank are referred to together as the “Banks”) and Jersey Shore State Bank’s wholly-owned subsidiary, The M Group, Inc. D/B/A The Comprehensive Financial Group (“The M Group”). The Company also owns a controlling interest in United Insurance Solutions, LLC. All significant inter-company balances and transactions have been eliminated in the consolidation. The interim financial statements are unaudited, but in the opinion of management reflect all adjustments necessary for the fair presentation of results for such periods. The results of operations for any interim period are not necessarily indicative of results for the full year. These financial statements should be read in conjunction with the financial statements and notes thereto contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018.
Newly Adopted Accounting Pronouncements and Recent Accounting Pronouncements	In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments, which changes the impairment model for most financial assets. This Update is intended to improve financial reporting by requiring timelier recording of credit losses on loans and other financial instruments held by financial institutions and other organizations. The underlying premise of the Update is that financial assets measured at amortized cost should be presented at the net amount expected to be collected, through an allowance for credit losses that is deducted from the amortized cost basis. The allowance for credit losses should reflect management’s current estimate of credit losses that are expected to occur over the remaining life of a financial asset. The income statement will be effected for the measurement of credit losses for newly recognized financial assets, as well as the expected increases or decreases of expected credit losses that have taken place during the period. ASU 2016-13 is effective for annual and interim periods beginning after December 15, 2019, and early adoption is permitted for annual and interim periods beginning after December 15, 2018. With certain exceptions, transition to the new requirements will be through a cumulative effect adjustment to opening retained earnings as of the beginning of the first reporting period in which the guidance is adopted. We expect to recognize a one-time cumulative effect adjustment to the allowance for loan losses as of the beginning of the first reporting period in which the new standard is effective, but cannot yet determine the magnitude of any such one-time adjustment or the overall impact of the new guidance on the consolidated financial statements. In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment. To simplify the subsequent measurement of goodwill, the FASB eliminated Step 2 from the goodwill impairment test. In computing the implied fair value of goodwill under Step 2, an entity had to perform procedures to determine the fair value at the impairment testing date of its assets and liabilities (including unrecognized assets and liabilities) following the procedure that would be required in determining the fair value of assets acquired and liabilities assumed in a business combination. Instead, under the amendments in this Update, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting units fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. A public business entity that is a U.S. Securities and Exchange Commission (SEC) filer should adopt the amendments in this Update for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. A public business entity that is not an SEC filer should adopt the amendments in this Update for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2020. All other entities, including not-for-profit entities, that are adopting the amendments in this Update should do so for their annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2021. This Update is not expected to have a significant impact on the Company’s financial statements. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes the Disclosure Requirements for Fair Value Measurements. The Update removes the requirement to disclose the amount of and reasons for transfers between Level I and Level II of the fair value hierarchy; the policy for timing of transfers between levels; and the valuation processes for Level III fair value measurements. The Update requires disclosure of changes in unrealized gains and losses for the period included in other comprehensive income (loss) for recurring Level III fair value measurements held at the end of the reporting period and the range and weighted average of significant unobservable inputs used to develop Level III fair value measurements. This Update is effective for all entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. This Update is not expected to have a significant impact on the Company’s financial statements. In August 2018, the FASB issued ASU 2018-14, Compensation - Retirement Benefits (Topic 715-20). This Update amends ASC 715 to add, remove and clarify disclosure requirements related to defined benefit pension and other postretirement plans. The Update eliminates the requirement to disclose the amounts in accumulated other comprehensive income expected to be recognized as part of net periodic benefit cost over the next year. The Update also removes the disclosure requirements for the effects of a one-percentage-point change on the assumed health care costs and the effect of this change in rates on service cost, interest cost and the benefit obligation for postretirement health care benefits. This Update is effective for public business entities for fiscal years ending after December 15, 2020, and must be applied on a retrospective basis. For all other entities, this Update is effective for fiscal years ending after December 15, 2021. This Update is not expected to have a significant impact on the Company’s financial statements. In August 2018, the FASB issued ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40). This Update addresses customers’ accounting for implementation costs incurred in a cloud computing arrangement that is a service contract and also adds certain disclosure requirements related to implementation costs incurred for internal-use software and cloud computing arrangements. The amendment aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). This Update is effective for public business entities for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years, with early adoption permitted. For all other entities, the amendments are effective for fiscal years beginning after December 15, 2020, and interim periods within fiscal years beginning after December 15, 2021. The amendments in this Update can be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. This Update is not expected to have a significant impact on the Company’s financial statements. In October 2018, the FASB issued ASU 2018-16, Derivatives and Hedging (Topic 815). The amendments in this Update permit use of the Overnight Index Swap (OIS) rate based on the Secured Overnight Financing Rate (SOFR) as a U.S. benchmark interest rate for hedge accounting purposes under Topic 815, in addition to the interest rates on direct Treasury obligations of the U.S. government, the London Interbank Offered Rate (LIBOR) swap rate, the OIS rate based on the Fed Funds Effective Rate, and the Securities Industry and Financial Markets Association (SIFMA) Municipal Swap Rate. For entities that have not already adopted Update 2017-12, the amendments in this Update are required to be adopted concurrently with the amendments in Update 2017-12. For public business entities that already have adopted the amendments in Update 2017-12, the amendments are effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. For all other entities that already have adopted the amendments in Update 2017-12, the amendments are effective for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years. Early adoption is permitted in any interim period upon issuance of this Update if an entity already has adopted Update 2017-12. This Update is not expected to have a significant impact on the Company’s financial statements. In November 2018, the FASB issued ASU 018-18, Collaborative Arrangements (Topic 808), which made the following targeted improvements to generally accepted accounting principles (GAAP) for collaborative arrangements (1) clarified that certain transactions between collaborative arrangement participants should be accounted for as revenue under Topic 606 when the collaborative arrangement participant is a customer in the context of a unit of account, (2) add unit-of-account guidance in Topic 808 to align with the guidance in Topic 606 (that is, a distinct good or service) when an entity is assessing whether the collaborative arrangement or a part of the arrangement is within the scope of Topic 606, and (3) require that in a transaction with a collaborative arrangement participant that is not directly related to sales to third parties, presenting the transaction together with revenue recognized under Topic 606 is precluded if the collaborative arrangement participant is not a customer. For public business entities, the amendments in this Update are effective for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years. For all other entities, the amendments are effective for fiscal years beginning after December 15, 2020, and interim periods within fiscal years beginning after December 15, 2021. This Update is not expected to have a significant impact on the Company’s financial statements. In March 2019, the FASB issued ASU 2019-01, Leases (Topic 842): Codification Improvements, which addressed issues lessors sometimes encounter. Specifically addressed in this Update were issues related to (1) determining the fair value of the underlying asset by the lessor that are not manufacturers or dealers (generally financial institutions and captive finance companies), and 2) lessors that are depository and lending institutions should classify principal and payments received under sales-type and direct financing leases within investing activities in the cash flow statement. The ASU also exempts both lessees and lessors from having to provide the interim disclosures required by ASC 250-10-50-3 in the fiscal year in which a company adopts the new leases standard. The amendments addressing the two lessor accounting issues are effective for public business entities for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years. For all other entities, the effective date is for fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020. This Update is not expected to have a significant impact on the Company’s financial statements. In April 2019, the FASB issued ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments – Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments, which affects a variety of topics in the Codification and applies to all reporting entities within the scope of the affected accounting guidance. The Company is currently evaluating the impact the adoption of the standard will have on the Company’s financial position or results of operations.

In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments, which changes the impairment model for most financial assets. This Update is intended to improve financial reporting by requiring timelier recording of credit losses on loans and other financial instruments held by financial institutions and other organizations. The underlying premise of the Update is that financial assets measured at amortized cost should be presented at the net amount expected to be collected, through an allowance for credit losses that is deducted from the amortized cost basis. The allowance for credit losses should reflect management’s current estimate of credit losses that are expected to occur over the remaining life of a financial asset. The income statement will be effected for the measurement of credit losses for newly recognized financial assets, as well as the expected increases or decreases of expected credit losses that have taken place during the period. ASU 2016-13 is effective for annual and interim periods beginning after December 15, 2019, and early adoption is permitted for annual and interim periods beginning after December 15, 2018. With certain exceptions, transition to the new requirements will be through a cumulative effect adjustment to opening retained earnings as of the beginning of the first reporting period in which the guidance is adopted. We expect to recognize a one-time cumulative effect adjustment to the allowance for loan losses as of the beginning of the first reporting period in which the new standard is effective, but cannot yet determine the magnitude of any such one-time adjustment or the overall impact of the new guidance on the consolidated financial statements.

In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment. To simplify the subsequent measurement of goodwill, the FASB eliminated Step 2 from the goodwill impairment test. In computing the implied fair value of goodwill under Step 2, an entity had to perform procedures to determine the fair value at the impairment testing date of its assets and liabilities (including unrecognized assets and liabilities) following the procedure that would be required in determining the fair value of assets acquired and liabilities assumed in a business combination. Instead, under the amendments in this Update, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting units fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. A public business entity that is a U.S. Securities and Exchange Commission (SEC) filer should adopt the amendments in this Update for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. A public business entity that is not an SEC filer should adopt the amendments in this Update for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2020. All other entities, including not-for-profit entities, that are adopting the amendments in this Update should do so for their annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2021. This Update is not expected to have a significant impact on the Company’s financial statements.

In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes the Disclosure Requirements for Fair Value Measurements. The Update removes the requirement to disclose the amount of and reasons for transfers between Level I and Level II of the fair value hierarchy; the policy for timing of transfers between levels; and the valuation processes for Level III fair value measurements. The Update requires disclosure of changes in unrealized gains and losses for the period included in other comprehensive income (loss) for recurring Level III fair value measurements held at the end of the reporting period and the range and weighted average of significant unobservable inputs used to develop Level III fair value measurements. This Update is effective for all entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. This Update is not expected to have a significant impact on the Company’s financial statements.

In August 2018, the FASB issued ASU 2018-14, Compensation - Retirement Benefits (Topic 715-20). This Update amends ASC 715 to add, remove and clarify disclosure requirements related to defined benefit pension and other postretirement plans. The Update eliminates the requirement to disclose the amounts in accumulated other comprehensive income expected to be recognized as part of net periodic benefit cost over the next year. The Update also removes the disclosure requirements for the effects of a one-percentage-point change on the assumed health care costs and the effect of this change in rates on service cost, interest cost and the benefit obligation for postretirement health care benefits. This Update is effective for public business entities for fiscal years ending after December 15, 2020, and must be applied on a retrospective basis. For all other entities, this Update is effective for fiscal years ending after December 15, 2021. This Update is not expected to have a significant impact on the Company’s financial statements.

In August 2018, the FASB issued ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40). This Update addresses customers’ accounting for implementation costs incurred in a cloud computing arrangement that is a service contract and also adds certain disclosure requirements related to implementation costs incurred for internal-use software and cloud computing arrangements. The amendment aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). This Update is effective for public business entities for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years, with early adoption permitted. For all other entities, the amendments are effective for fiscal years beginning after December 15, 2020, and interim periods within fiscal years beginning after December 15, 2021. The amendments in this Update can be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. This Update is not expected to have a significant impact on the Company’s financial statements.

In October 2018, the FASB issued ASU 2018-16, Derivatives and Hedging (Topic 815). The amendments in this Update permit use of the Overnight Index Swap (OIS) rate based on the Secured Overnight Financing Rate (SOFR) as a U.S. benchmark interest rate for hedge accounting purposes under Topic 815, in addition to the interest rates on direct Treasury obligations of the U.S. government, the London Interbank Offered Rate (LIBOR) swap rate, the OIS rate based on the Fed Funds Effective Rate, and the Securities Industry and Financial Markets Association (SIFMA) Municipal Swap Rate. For entities that have not already adopted Update 2017-12, the amendments in this Update are required to be adopted concurrently with the amendments in Update 2017-12. For public business entities that already have adopted the amendments in Update 2017-12, the amendments are effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. For all other entities that already have adopted the amendments in Update 2017-12, the amendments are effective for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years. Early adoption is permitted in any interim period upon issuance of this Update if an entity already has adopted Update 2017-12. This Update is not expected to have a significant impact on the Company’s financial statements.

In November 2018, the FASB issued ASU 018-18, Collaborative Arrangements (Topic 808), which made the following targeted improvements to generally accepted accounting principles (GAAP) for collaborative arrangements (1) clarified that certain transactions between collaborative arrangement participants should be accounted for as revenue under Topic 606 when the collaborative arrangement participant is a customer in the context of a unit of account, (2) add unit-of-account guidance in Topic 808 to align with the guidance in Topic 606 (that is, a distinct good or service) when an entity is assessing whether the collaborative arrangement or a part of the arrangement is within the scope of Topic 606, and (3) require that in a transaction with a collaborative arrangement participant that is not directly related to sales to third parties, presenting the transaction together with revenue recognized under Topic 606 is precluded if the collaborative arrangement participant is not a customer. For public business entities, the amendments in this Update are effective for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years. For all other entities, the amendments are effective for fiscal years beginning after December 15, 2020, and interim periods within fiscal years beginning after December 15, 2021. This Update is not expected to have a significant impact on the Company’s financial statements.

In March 2019, the FASB issued ASU 2019-01, Leases (Topic 842): Codification Improvements, which addressed issues lessors sometimes encounter. Specifically addressed in this Update were issues related to (1) determining the fair value of the underlying asset by the lessor that are not manufacturers or dealers (generally financial institutions and captive finance companies), and 2) lessors that are depository and lending institutions should classify principal and payments received under sales-type and direct financing leases within investing activities in the cash flow statement. The ASU also exempts both lessees and lessors from having to provide the interim disclosures required by ASC 250-10-50-3 in the fiscal year in which a company adopts the new leases standard. The amendments addressing the two lessor accounting issues are effective for public business entities for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years. For all other entities, the effective date is for fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020. This Update is not expected to have a significant impact on the Company’s financial statements.

In April 2019, the FASB issued ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments – Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments, which affects a variety of topics in the Codification and applies to all reporting entities within the scope of the affected accounting guidance. The Company is currently evaluating the impact the adoption of the standard will have on the Company’s financial position or results of operations.