| Name | GuarantyFeeIncome |
|---|---|
| Namespace | http://fasb.org/us-gaap/2020-01-31 |
| Prefix | us-gaap |
| Data type | xbrli:monetaryItemType |
| Period type | duration |
| Substitution Group | xbrli:item |
| Balance | credit |
| Nillable | True |
| Abstract | False |
| Text | Lang | Role | Container role |
|---|---|---|---|
| Guaranty Fee Income (Deprecated 2018-01-31) | en-US | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| This item represents the portion of monthly guaranty fees collected representing the interest imputed and recognized under the prospective interest method on the present value of the contractually stipulated guarantee payments at inception of the contract. | en-US | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Name | Value | Role |
|---|---|---|
| DeprecatedDate | 2018-01-31 | http://fasb.org/srt/role/changeNote/changeNote |
| DeprecatedLabel | Element was deprecated because the financial reporting concept can be conveyed dimensionally. | http://fasb.org/srt/role/changeNote/changeNote |
| DeprecationReplacement | srt:ProductOrServiceAxis GuaranteesMember RevenueFromContractWithCustomerIncludingAssessedTax | http://fasb.org/srt/role/changeNote/changeNote |
| SourceName | Revenue | http://fasb.org/srt/role/changeNote/changeNote |
| TaxonomyVersion | 2018 | http://fasb.org/srt/role/changeNote/changeNote |
| ChangeDate | 2017-11 | http://fasb.org/srt/role/changeNote/changeNote |
| ElementDeprecated | true | http://fasb.org/srt/role/changeNote/changeNote |
| Source_ASU_Number | 2014-09 | http://fasb.org/srt/role/changeNote/changeNote |
| Name | Relation Type | Role | |
|---|---|---|---|
us-gaap:DeprecatedItems | parent-child | http://fasb.org/us-gaap/role/deprecated/deprecated | |
us-gaap:GuaranteesMember | dep-dimensionallyQualifiedConcept-deprecatedConcept | http://fasb.org/us-gaap/role/deprecated/deprecated | |
srt:ProductOrServiceAxis | dep-dimensionallyQualifiedConcept-deprecatedConcept | http://fasb.org/us-gaap/role/deprecated/deprecated | |
us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax | dep-dimensionallyQualifiedConcept-deprecatedConcept | http://fasb.org/us-gaap/role/deprecated/deprecated |