Name:	ovly_CapitalConservationBuffer
Namespace Prefix:	ovly_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The minimum common equity tier 1 risk based capital ratio (common equity tier 1 capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

No definition available.

Name:	ovly_CommonEquityTier1CapitalRequiredForCapitalAdequacyToRiskWeightedAssets
Namespace Prefix:	ovly_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations and by a bank that has received the highest rating by regulators.

No definition available.

Name:	ovly_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsHighestRatedBanks
Namespace Prefix:	ovly_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The amount above the minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

No definition available.

Name:	ovly_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsPercentageAboveMinimum
Namespace Prefix:	ovly_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

Name:	us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826