Stockholders' Equity (Deficit) - Summary of Preferred Stock Allocated to Investors (Detail) - Penelope Mining LLC [Member]	Sep. 30, 2016 USD ($) $ / shares shares
Preferred Stock [Line Items]
Shares \| shares	15,650,149
Investment \| $	$ 144,462,918
Series AA-1 Convertible Preferred Stock [Member]
Preferred Stock [Line Items]
Shares \| shares	8,427,004
Price Per Share \| $ / shares	$ 12.00
Investment \| $	$ 101,124,048
Series AA-2 Convertible Preferred Stock [Member]
Preferred Stock [Line Items]
Shares \| shares	7,223,145
Price Per Share \| $ / shares	$ 6.00
Investment \| $	$ 43,338,870

Preferred Stock [Line Items]

No definition available.

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- Definition

Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Aggregate par or stated value of issued nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable preferred shares, par value and other disclosure concepts are in another section within stockholders' equity.

+ References

+ Details

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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- Details

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