British Pound Sterling Deposits - Additional Information (Detail)	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($)	Mar. 31, 2020 GBP (£)	Mar. 31, 2019 USD ($)	Dec. 31, 2019 GBP (£)	Mar. 31, 2020 GBP (£)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 GBP (£)
Cash And Cash Equivalents [Abstract]
Principal deposits	$ 49,676,038	£ 19,388,364	$ 18,986,604	£ 121,214,247
Principal redemptions	25,254,708	19,389,965	$ 31,438,493	101,821,260
Cash paid for Sponsor's fee		£ 14,730		£ 54,267
Deposits, interest bearing	$ 156,269,080				£ 126,028,514	$ 141,290,062	£ 126,044,845
Annual nominal rate	0.00%				0.00%

Payments for sponsor's fee.

No definition available.

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=118262064&loc=SL116631418-115840

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=118262064&loc=SL116631419-115840

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- References

No definition available.

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- Definition

Rate of interest on investment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

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-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 2
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- Definition

The cash outflow for reacquisition of callable preferred stock.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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The cash inflow from issuance of preferred stock that is classified as callable.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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