Japanese Yen Deposits	12 Months Ended
Dec. 31, 2020
Cash And Cash Equivalents [Abstract]
Japanese Yen Deposits	Note 4 - Japanese Yen Deposits Japanese Yen principal deposits are held in a Japanese Yen-denominated, interest-bearing demand account. The interest rate in effect as of December 31, 2020 was an annual nominal rate of -0.20%. For the year ended December 31, 2020, there were Japanese Yen principal deposits of 24,652,512,877, Japanese Yen principal redemptions of 19,901,290,156 and Japanese Yen withdrawals (to pay expenses) of 153,028,653, resulting in an ending Japanese Yen principal balance of 25,507,068,457. This equates to 247,053,789 USD. For the year ended December 31, 2019, there were Japanese Yen principal deposits of 38,151,608,760, Japanese Yen principal redemptions of 36,228,131,318 and Japanese Yen withdrawals (to pay expenses) of 119,473,200, resulting in an ending Japanese Yen principal balance of 20,908,874,389. This equates to 192,398,201 USD (which includes USD subscriptions receivable). Net interest, if any, associated with creation and redemption activity is held in a Japanese Yen-denominated non-interest-bearing account, and any balance is distributed in full as part of the monthly income distributions, if any.

The entire disclosure for cash and cash equivalent footnotes, which may include the types of deposits and money market instruments, applicable carrying amounts, restricted amounts and compensating balance arrangements. Cash and equivalents include: (1) currency on hand (2) demand deposits with banks or financial institutions (3) other kinds of accounts that have the general characteristics of demand deposits (4) short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments maturing within three months from the date of acquisition qualify.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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