| Label | Element | Value |
|---|---|---|
| Risk/Return: | rr_RiskReturnAbstract | Â |
| Document Type | dei_DocumentType | 485BPOS |
| Document Period End Date | dei_DocumentPeriodEndDate | Dec. 31, 2010 |
| Registrant Name | dei_EntityRegistrantName | Old Mutual Funds II |
| Central Index Key | dei_EntityCentralIndexKey | 0000775180 |
| Amendment Flag | dei_AmendmentFlag | false |
| Document Creation Date | dei_DocumentCreationDate | May 20, 2011 |
| Document Effective Date | dei_DocumentEffectiveDate | May 20, 2011 |
| Prospectus Date | rr_ProspectusDate | May 20, 2011 |