| 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 | Amount before tax of other than temporary impairment (OTTI) on investment in held-to-maturity debt security, recognized in other comprehensive loss. | 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 | 220 | http://fasb.org/us-gaap/role/ref/legacyRef |
| SubTopic | 10 | http://fasb.org/us-gaap/role/ref/legacyRef |
| Section | 45 | http://fasb.org/us-gaap/role/ref/legacyRef |
| Paragraph | 14A | http://fasb.org/us-gaap/role/ref/legacyRef |
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| Name | Accounting Standards Codification | http://fasb.org/us-gaap/role/ref/legacyRef |
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