Subsequent Events (Details Textual) - Subsequent Event - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended
Apr. 28, 2017	Sep. 30, 2017
Nesscap Energy, Inc \| Common Stock
Subsequent Event [Line Items]
Number of shares issued	4.1
Value of share consideration	$ 25.3
Percentage of outstanding shares	11.30%
Scenario, Forecast \| Stock Purchase Agreement \| SDIC Fund Management Co., Ltd. \| Investor
Subsequent Event [Line Items]
Investor ownership percentage		19.90%
Scenario, Forecast \| Stock Purchase Agreement \| SDIC Fund Management Co., Ltd. \| Investor \| Maximum
Subsequent Event [Line Items]
Investor ownership percentage		19.90%
Scenario, Forecast \| Stock Purchase Agreement \| SDIC Fund Management Co., Ltd.
Subsequent Event [Line Items]
Number of shares to be sold pursuant to stock purchase agreement		7.4
Sales price per share		$ 6.32
Aggregate purchase price		$ 46.6

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

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- Definition

Amount of consideration received by subsidiary or equity investee in exchange for shares of stock issued or sold. Includes amount of cash received, fair value of noncash assets received, and fair value of liabilities assumed by the investor.

+ References

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

+ References

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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