FDIC Indemnification Asset and True-up Payment Obligation (FDIC Indemnification Expense) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Fdic Shared Loss Expense [Abstract]
FDIC indemnification asset, expense	$ 0	$ (1,910)	$ (1,403)	$ 6,179
Change in true-up payment obligation expense	0	(508)	0	(1,621)
Reimbursement to FDIC for recoveries	0	(878)	0	(2,945)
FDIC shared-loss expense, net	$ 0	$ (3,296)	$ 1,403	$ (10,745)

Increases to the indemnification asset due to accretion of the loan discount relating to loss sharing agreements with the Federal Deposit Insurance Corporation (FDIC), excluding the clawback provision.

No definition available.

Name:	ofg_FdicIndemnificationAssetExpense
Namespace Prefix:	ofg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration