| Standard label: | Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities, Portion Recognized in Earnings, Net, Qualitative Disclosures, Methodology |
| Name: | us-gaap:OtherThanTemporaryImpairmentLossesInvestmentsHeldtomaturitySecuritiesPortionRecognizedInEarningsNetQualitativeDisclosuresMethodology |
| Documentation: | This item represents a discussion, by major security type, of the methodology used to determine the amount of the other than temporary impairment (OTTI) related to credit loss of a debt security categorized as held-to-maturity when only the amount related to a credit loss was recognized in earnings. |
| Object type: | cm:Concept |
| Data type: | Text/String (xbrli:stringItemType) |
| Period type: | For Period (duration) |
| Balance type: | (no balance type) |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:OtherThanTemporaryImpairmentLossesInvestmentsHeldtomaturitySecuritiesPortionRecognizedInEarningsNetQualitativeDisclosuresMethodology |
| Label | Role | Language |
| Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities, Portion Recognized in Earnings, Net, Qualitative Disclosures, Methodology | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 320 10 50 8A | http://fasb.org/us-gaap/role/ref/legacyRef | 320 |