ACQUISITION OF LUZERNE NATIONAL BANK CORPORATION (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	Jun. 01, 2013 USD ($) loan_office branch_office $ / shares shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($)
Acquisition of Luzerne National Bank Corporation
Purchased credit-impaired loans		$ 15,883	$ 17,576
Loan portfolio without evidence of deterioration		1,033,163	905,000
Adjustments to reflect liabilities acquired at fair value:
Goodwill resulting from merger		$ 17,104	$ 17,104
Luzerne National Bank Corporation
Acquisition of Luzerne National Bank Corporation
Number of branch offices acquired | branch_office	8
Number of loan production offices acquired | loan_office	1
Percentage of the total shares outstanding, issued		20.62%
Purchased credit-impaired loans	$ 1,211
Non-accretable difference on purchased credit-impaired loans	842
Loan portfolio without evidence of deterioration	249,789
Loan portfolio without evidence of deterioration at fair value	$ 249,500
Purchase Price Consideration in Common Stock
Luzerne National Bank Corporation common shares settled for stock (in shares) | shares	630,216
Exchange Ratio	1.5534
Penns Woods Bancorp, Inc. shares issued (in shares) | shares	978,977	978,977
Value assigned to Penns Woods Bancorp, Inc. common share (in dollars per share) | $ / shares	$ 40.59
Purchase price assigned to Luzerne National Bank Corporation common shares exchanged for Penns Woods Bancorp, Inc.	$ 39,736
Purchase Price Consideration - Cash for Common Stock
Luzerne National Bank Corporation shares exchanged for cash (in shares) | shares	46,480
Purchase price paid to each Luzerne National Bank Corporation common share exchanged for cash (in dollars per share) | $ / shares	$ 61.86
Purchase price assigned to Luzerne National Bank Corporation common shares exchanged for cash	$ 2,876
Purchase price	42,612
Net Assets Acquired:
Luzerne National Bank Corporation shareholders’ equity	27,371
Adjustments to reflect assets acquired at fair value:
Investments	33
Loans
Interest rate	2,680
General credit	(3,206)
Specific credit - non-amortizing	(58)
Specific credit - amortizing	(40)
Core deposit intangible	1,882
Trade name intangible	133
Owned premises	1,138
Leased premises contracts	122
Deferred tax assets	(603)
Adjustments to reflect liabilities acquired at fair value:
Time deposits	(912)
Net assets acquired	28,540
Goodwill resulting from merger	$ 14,072