Increase decrease in prior period accrued interest expense.

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Prior period accrued sponsor fee increase decrease.

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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.

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Amount of increase (decrease) in cash, cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; including effect from exchange rate change. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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.

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Amount of effect of exchange rate changes on cash balances held in foreign currencies. Excludes cash equivalents.

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Amount of increase (decrease) from effect of exchange rate changes on cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; held in foreign currencies. Excludes amounts for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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.

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The increase (decrease) during the reporting period in the aggregate amount of obligations to be paid to the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entities' management; an entity and its principal owners, management, or member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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The increase (decrease) during the reporting period in interest payable, which represents the amount owed to note holders, bond holders, and other parties for interest earned on loans or credit extended to the reporting entity.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Total amount of cash paid for operating activities during the current period.

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The cash outflow for reacquisition of callable preferred stock.

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The cash inflow from issuance of preferred stock that is classified as callable.

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Total amount of cash received from operating activities during the current period.

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Comparative Data for the Two Months Ended December 31, 2017 (Unaudited) - Comparative Data for Statements of Cash Flows (Detail)	2 Months Ended			3 Months Ended								12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2018 JPY (¥)	Dec. 31, 2017 USD ($)	Oct. 31, 2018 USD ($)	Jul. 31, 2018 USD ($)	Apr. 30, 2018 USD ($)	Jan. 31, 2018 USD ($)	Oct. 31, 2017 USD ($)	Jul. 31, 2017 USD ($)	Apr. 30, 2017 USD ($)	Jan. 31, 2017 USD ($)	Oct. 31, 2018 USD ($)	Oct. 31, 2018 JPY (¥)	Oct. 31, 2017 USD ($)	Oct. 31, 2017 JPY (¥)
Cash flows from operating activities
Cash received for accrued income			$ 0
Cash paid for expenses	(109,230)	¥ (12,310,233)	(93,462)									(696,256)	¥ (76,898,821)	(591,577)	¥ (66,298,233)
Net cash used in operating activities	(109,230)		(93,462)									(696,256)		(591,577)
Cash flows from financing activities
Cash received to purchase redeemable Shares	38,046,882	4,776,165,855	8,504,960									112,839,783	12,462,736,515	283,768,433	31,802,013,465
Cash paid to redeem redeemable Shares		¥ 0	(17,009,104)									(99,745,024)	¥ (10,536,230,459)	(270,838,173)	¥ (30,833,153,795)
Net cash used in financing activities	38,046,882		(8,504,144)									13,094,759		12,930,260
Adjustment to period cash flows due to currency movement	4,767,660		973,174									519,315		(8,462,494)
Decrease in cash	42,705,312		(7,624,432)									12,917,818		3,876,189
Cash at beginning of period/year	127,074,693		114,156,875				$ 114,156,875				$ 110,280,686	114,156,875		110,280,686
Cash at end of period/year	169,780,005		106,532,443	$ 127,074,693				$ 114,156,875				127,074,693		114,156,875
Reconciliation of net comprehensive income to net cash provided by operating activities
Net Comprehensive Loss	(122,840)		(91,379)	$ (161,150)	$ (204,814)	$ (197,879)	$ (140,590)	$ (145,076)	$ (152,159)	$ (143,771)	$ (151,186)	(704,433)		(592,192)
Adjustments to reconcile net comprehensive loss to net cash used in operating activities:
Effect of exchange rate on cash	(1,919)		(406)									1,425		3,756
Accrued Sponsor's fee	55,665		36,418									43,161		37,756
Accrued interest expense on currency deposits	13,968		9,257									10,943		9,596
Prior period accrued Sponsor's fee	(43,161)		(37,756)									(37,756)		(40,116)
Prior period accrued interest expense on currency deposits	(10,943)		(9,596)									(9,596)		(10,377)
Net cash used in operating activities	$ (109,230)		$ (93,462)									$ (696,256)		$ (591,577)