Impaired financing receivable, accrued interest receivable.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Impaired financing receivable allowance for uncollectible accrued interest receivable.

+ References

No definition available.

+ Details

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Namespace Prefix:	opbk_
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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

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

- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

+ Details

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

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

+ Details

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Balance Type:	credit
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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Period Type:	duration

- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

+ Details

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

- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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- Definition

Amount, before allowance for credit loss, of financing receivable.

+ References

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+ Details

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- Details

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- Details

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- Details

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Loans and Allowance for Loan Losses - Schedule of Allowance for Loan Losses and Recorded Investment by Portfolio Segment and Impairment Methodology (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loans Individually Evaluated for Impairment	$ 429		$ 417
Allowance for Loan Collectively Evaluated for Impairment	13,705		14,935
Total	14,134	$ 14,687	15,352	$ 14,164	$ 12,764	$ 10,050
Loans Individually Evaluated for Impairment	872		504
Loans Collectively Evaluated for Impairment	1,235,073		1,103,604
Total	1,235,945		1,104,108
Allowance for uncollectible accrued interest receivable	465		643
Accrued interest receivable	4,100		4,400
Commercial Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loans Individually Evaluated for Impairment	0		0
Allowance for Loan Collectively Evaluated for Impairment	8,215		8,505
Total	8,215	8,456	8,505	8,139	7,145	6,000
Loans Individually Evaluated for Impairment	0		0
Loans Collectively Evaluated for Impairment	690,391		654,235
Total	690,391		654,235
SBA Loans Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loans Individually Evaluated for Impairment	109		0
Allowance for Loan Collectively Evaluated for Impairment	1,987		1,802
Total	2,096	1,997	1,802	1,758	1,346	939
Loans Individually Evaluated for Impairment	552		0
Loans Collectively Evaluated for Impairment	218,950		136,873
Total	219,502		136,873
SBA Loans Non- Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loans Individually Evaluated for Impairment	0		87
Allowance for Loan Collectively Evaluated for Impairment	196		191
Total	196	228	278	271	253	121
Loans Individually Evaluated for Impairment	0		174
Loans Collectively Evaluated for Impairment	85,644		75,477
Total	85,644		75,651
Commercial and Industrial
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loans Individually Evaluated for Impairment	320		330
Allowance for Loan Collectively Evaluated for Impairment	1,634		2,233
Total	1,954	2,286	2,563	1,915	1,920	1,289
Loans Individually Evaluated for Impairment	320		330
Loans Collectively Evaluated for Impairment	123,384		107,175
Total	123,704		107,505
Home Mortgage
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loans Individually Evaluated for Impairment	0		0
Allowance for Loan Collectively Evaluated for Impairment	1,658		2,185
Total	1,658	1,704	2,185	2,059	2,074	1,667
Loans Individually Evaluated for Impairment	0		0
Loans Collectively Evaluated for Impairment	115,653		128,683
Total	115,653		128,683
Consumer
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loans Individually Evaluated for Impairment	0		0
Allowance for Loan Collectively Evaluated for Impairment	15		19
Total	15	$ 16	19	$ 22	$ 26	$ 34
Loans Individually Evaluated for Impairment	0		0
Loans Collectively Evaluated for Impairment	1,051		1,161
Total	$ 1,051		$ 1,161