XML 19 R4.htm IDEA: XBRL DOCUMENT v3.19.2

Condensed Schedule of Investments (Parenthetical)	6 Months Ended
	Jun. 30, 2019 USD ($)
Collateral Amount On Open Futures Contracts	$ 64,862,897
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.47%, 7/05/2019 [Member]
Interest rate	2.47%
Expiration date	7/05/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.48%, 7/11/2019 [Member]
Interest rate	2.48%
Expiration date	7/11/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.47%, 7/18/2019 [Member]
Interest rate	2.47%
Expiration date	7/18/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.47%, 7/25/2019 [Member]
Interest rate	2.47%
Expiration date	7/25/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.48%, 8/01/2019 [Member]
Interest rate	2.48%
Expiration date	8/01/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.46%, 8/08/2019 [Member]
Interest rate	2.46%
Expiration date	8/08/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.47%, 8/15/2019 [Member]
Interest rate	2.47%
Expiration date	8/15/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.47%, 8/22/2019 [Member]
Interest rate	2.47%
Expiration date	8/22/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.48%, 8/29/2019 [Member]
Interest rate	2.48%
Expiration date	8/29/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.48%, 9/05/2019 [Member]
Interest rate	2.48%
Expiration date	9/05/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.48%, 9/12/2019 [Member]
Interest rate	2.48%
Expiration date	9/12/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.46%, 9/19/2019 [Member]
Interest rate	2.46%
Expiration date	9/19/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.41%, 9/26/2019 [Member]
Interest rate	2.41%
Expiration date	9/26/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.40%, 10/03/2019 [Member]
Interest rate	2.40%
Expiration date	10/03/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.41%, 10/10/2019 [Member]
Interest rate	2.41%
Expiration date	10/10/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.40%, 10/24/2019 [Member]
Interest rate	2.40%
Expiration date	10/24/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.37%, 10/31/2019 [Member]
Interest rate	2.37%
Expiration date	10/31/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.40%, 11/07/2019 [Member]
Interest rate	2.40%
Expiration date	11/07/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.38%, 11/14/2019 [Member]
Interest rate	2.38%
Expiration date	11/14/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.37%, 11/21/2019 [Member]
Interest rate	2.37%
Expiration date	11/21/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.33%, 11/29/2019 [Member]
Interest rate	2.33%
Expiration date	11/29/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.20%, 12/05/2019 [Member]
Interest rate	2.20%
Expiration date	12/05/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.16%, 12/12/2019 [Member]
Interest rate	2.16%
Expiration date	12/12/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.15%, 12/19/2019 [Member]
Interest rate	2.15%
Expiration date	12/19/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.07%, 12/26/2019 [Member]
Interest rate	2.07%
Expiration date	12/26/2019

X

- Definition

The collateral amount on open future contracts.

+ References

No definition available.

+ Details

Name:	ung_CollateralAmountOnOpenFuturesContracts
Namespace Prefix:	ung_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

The list of dates or date range within which the options may be exercised of the investment subject to option.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 5
-Subparagraph (SX 210.12-13.5(d))
-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611282-123010

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 6
-Subparagraph (SX 210.12-14.4(b))
-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611322-123010

+ Details

Name:	us-gaap_InvestmentOwnedSubjectToOptionExerciseDates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	invest_InvestmentAxis=us-gaap_CashEquivalentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesClassAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsFifteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsSixteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsSeventeenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsEighteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsNineteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsTwentyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsTwentyOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsTwentyTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsTwentyThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsTwentyFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsTwentyFiveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsTwentySixMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsTwentySevenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsTwentyEightMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsTwentyNineMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsThirtyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsThirtyOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsThirtyTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsThirtyThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsThirtyFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsThirtyFiveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsThirtySixMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsThirtysevenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsThirtynineMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	invest_InvestmentSecuritiesSeriesAxis=ung_UsTreasuryBillsFortyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: