XML 22 R7.htm IDEA: XBRL DOCUMENT
v3.22.4

Statements of Operations (Parenthetical) | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Statements of Operations |  |  |
Interest income | 5.00% | 5.00% | 5.00%

X
- Definition The maximum percentage of paid in kind amount of interest income. + References No definition available. + Details
Name: | ung_InterestIncomeMaximumPercentageOfPaidInKind
Namespace Prefix: | ung_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_IncomeStatementAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration