Subsidiary Guarantors - Condensed Consolidating Balance Sheet - Additional Information (Details) - $ / shares	Jun. 30, 2017	Dec. 31, 2016
Mezzanine equity
Series A preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Series A preferred stock, shares issued	1,840,000	1,840,000
Series A preferred stock, shares outstanding	1,840,000	1,840,000
Treasury stock
Treasury stock, shares	22,602	22,602
Class A common stock
Common stock
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares issued	66,671,659	57,048,076
Common stock, shares outstanding	66,649,057	57,025,474
Class B common stock
Common stock
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares issued	29,823,927	29,832,098
Common stock, shares outstanding	29,823,927	29,832,098
JEI (Parent)
Mezzanine equity
Series A preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Series A preferred stock, shares issued	1,840,000	1,840,000
Series A preferred stock, shares outstanding	1,840,000	1,840,000
Treasury stock
Treasury stock, shares	22,602	22,602
JEI (Parent) \| Class A common stock
Common stock
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares issued	66,671,659	57,048,076
Common stock, shares outstanding	66,649,057	57,025,474
JEI (Parent) \| Class B common stock
Common stock
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares issued	29,823,927	29,832,098
Common stock, shares outstanding	29,823,927	29,832,098

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Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Per share amount of par value or stated value of stock classified as temporary equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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