| PublishDate | 2018-01 | http://fasb.org/us-gaap/role/tin/taxonomyImplementationNote |
| Positive_XBRL_Value | Enter a positive XBRL value for gain. | http://fasb.org/us-gaap/role/tin/taxonomyImplementationNote |
| Negative_XBRL_Value | Enter a negative XBRL value for loss. | http://fasb.org/us-gaap/role/tin/taxonomyImplementationNote |
| SourceName | Financial Instruments-Recognition and Measurement | http://fasb.org/srt/role/changeNote/changeNote |
| TaxonomyVersion | 2018 | http://fasb.org/srt/role/changeNote/changeNote |
| ChangeDate | 2017-08 | http://fasb.org/srt/role/changeNote/changeNote |
| ModifiedLabels | true | http://fasb.org/srt/role/changeNote/changeNote |
| ModifiedDocumentation | true | http://fasb.org/srt/role/changeNote/changeNote |
| PreviousDocumentation | This item represents the unrealized gain (loss) related to held-to-maturity securities transferred to another category of investments in debt and equity securities (trading or available-for-sale). | http://fasb.org/srt/role/changeNote/changeNote |
| Source_ASU_Number | 2016-01 | http://fasb.org/srt/role/changeNote/changeNote |
| Publisher | FASB | http://fasb.org/us-gaap/role/ref/legacyRef |
| Name | Accounting Standards Codification | http://fasb.org/us-gaap/role/ref/legacyRef |
| Topic | 320 | http://fasb.org/us-gaap/role/ref/legacyRef |
| SubTopic | 10 | http://fasb.org/us-gaap/role/ref/legacyRef |
| Section | 50 | http://fasb.org/us-gaap/role/ref/legacyRef |
| Paragraph | 10 | http://fasb.org/us-gaap/role/ref/legacyRef |
| Subparagraph | (c) | http://fasb.org/us-gaap/role/ref/legacyRef |
| URI | http://asc.fasb.org/extlink&oid=121645371&loc=d3e27405-111563 | http://fasb.org/us-gaap/role/ref/legacyRef |