Stockholders’ (Deficit)/Equity	12 Months Ended
Dec. 31, 2017
Stockholders' Equity Note [Abstract]
Stockholders’ (Deficit)/Equity	Stockholders’ (Deficit)/Equity From January 1, 2015 through December 31, 2015, Synergy sold 3,435,998 shares of common stock, pursuant to the ATM Agreement with Cantor, yielding gross proceeds of $14.7 million, at an average selling price of $4.27 per share. Selling agent fees related to above financings from January 1, 2015 through December 31, 2015 were $0.4 million. On June 8, 2015, Synergy amended its Articles of Incorporation and increased the number of shares of its common stock authorized for issuance from 200,000,000 to 350,000,000 shares. On July 2, 2015, Synergy filed a “shelf” registration statement on Form S-3 to offer and sell, from time to time in one or more offerings, any combination of common stock, preferred stock, debt securities, warrants to purchase common stock, preferred stock or debt securities, or any combination of the foregoing, either individually or as units comprised of one or more of the other securities, having an aggregate initial offering price not exceeding $250,000,000. From January 1, 2015 through December 31, 2015 warrants to purchase 189,412 shares of common stock were exercised, yielding proceeds to the Company of $1.0 million. In addition employee stock options to purchase 269,720 shares of common stock were exercised yielding proceeds of $1.1 million. On March 18, 2016, Synergy entered into an exchange agreement for the exchange of $79.8 million in aggregate principal amount of the Notes, representing approximately 50% of the outstanding aggregate principal amount of Notes, for 35.3 million shares of Synergy's common stock, with a total of 25.6 million shares representing the conversion price of $3.11 pursuant to the existing terms of the Notes. Synergy also issued approximately 872,000 shares at the five day average share price of $2.81 in payment of accrued and unpaid interest of $2.4 million on Notes accepted in the Exchanges, with such shares included in the Shares issued in connection with conversion of Senior Convertible Debentures in the Consolidated Statement of Changes in Stockholders' Equity/(Deficit). In addition, Synergy issued 9.6 million shares of common stock as an inducement for Note holders to convert their Notes into Synergy common stock and recognized debt conversion expense of $25.6 million in the exchange. In November 2016 Synergy exchanged $55.7 million in aggregate principal amount of the Notes, representing approximately 70% of the outstanding aggregate principal amount of Notes, for 20.5 million shares of Synergy's common stock, with a total of 17.9 million shares representing the conversion price of $3.11 pursuant to the existing terms of the Notes. The amortization of deferred debt costs was accelerated consistent with the 70% reduction of aggregate principal amount this transaction represented, and resulted in additional interest expense of approximately $2 million. The Company recognized debt conversion expense of $14.5 million representing 2.6 million shares in the exchange. From January 1, 2016 through December 31, 2016, $135.5 million aggregate principal amount of the Notes was converted into approximately 56.6 million shares of Synergy common stock. On May 5, 2016, Synergy announced that it had entered into definitive agreements with certain institutional investors to sell 29,948,334 shares of common stock at a price of $3.00 per share. The shares were offered and sold directly to institutional investors by the Company in a registered direct offering conducted without an underwriter or placement agent. The gross proceeds from the offering were approximately $89.8 million. The offering closed on May 6, 2016. From January 1, 2016 through December 31, 2016 warrants to purchase 2,430,656 shares of common stock were exercised, yielding proceeds to us of $11.3 million. On January 31, 2017, Synergy entered into an underwriting agreement with Cantor Fitzgerald & Co., as representative of several underwriters, to issue and sell 20,325,204 shares of common stock of the Company in an underwritten public offering pursuant to a Registration Statement on Form S-3 and a related prospectus and prospectus supplement, in each case filed with the Securities and Exchange Commission (the “Offering”). The public offering price was $6.15 per share of Common Stock. The Offering closed on February 6, 2017, yielding net proceeds of approximately $121.6 million, after deducting underwriting discounts and commissions and offering expenses payable by the Company. On June 27, 2017, Synergy increased the number of shares of common stock authorized for issuance from 350,000,000 to 400,000,000. On November 13, 2017, Synergy entered into an underwriting agreement with Jefferies LLC, as representative of the several underwriters, to issue and sell 21,705,426 shares of common stock of the Company together with accompanying warrants (“Warrants”) to purchase an aggregate of 21,705,426 shares of Common Stock in an underwritten offering pursuant to a Registration Statement on Form S-3ASR and a related prospectus and prospectus supplement, in each case filed with the Securities and Exchange Commission (the “Offering”). The offering price was $2.58 per share of Common Stock and accompanying Warrant. Net proceeds from the Offering were approximately $52.2 million, after deducting underwriting discounts and commissions and offering expenses payable by the Company.

Stockholders’ (Deficit)/Equity

From January 1, 2015 through December 31, 2015, Synergy sold 3,435,998 shares of common stock, pursuant to the ATM Agreement with Cantor, yielding gross proceeds of $14.7 million, at an average selling price of $4.27 per share. Selling agent fees related to above financings from January 1, 2015 through December 31, 2015 were $0.4 million.

On June 8, 2015, Synergy amended its Articles of Incorporation and increased the number of shares of its common stock authorized for issuance from 200,000,000 to 350,000,000 shares.

On July 2, 2015, Synergy filed a “shelf” registration statement on Form S-3 to offer and sell, from time to time in one or more offerings, any combination of common stock, preferred stock, debt securities, warrants to purchase common stock, preferred stock or debt securities, or any combination of the foregoing, either individually or as units comprised of one or more of the other securities, having an aggregate initial offering price not exceeding $250,000,000.

From January 1, 2015 through December 31, 2015 warrants to purchase 189,412 shares of common stock were exercised, yielding proceeds to the Company of $1.0 million. In addition employee stock options to purchase 269,720 shares of common stock were exercised yielding proceeds of $1.1 million.

On March 18, 2016, Synergy entered into an exchange agreement for the exchange of $79.8 million in aggregate principal amount of the Notes, representing approximately 50% of the outstanding aggregate principal amount of Notes, for 35.3 million shares of Synergy's common stock, with a total of 25.6 million shares representing the conversion price of $3.11 pursuant to the existing terms of the Notes. Synergy also issued approximately 872,000 shares at the five day average share price of $2.81 in payment of accrued and unpaid interest of $2.4 million on Notes accepted in the Exchanges, with such shares included in the Shares issued in connection with conversion of Senior Convertible Debentures in the Consolidated Statement of Changes in Stockholders' Equity/(Deficit). In addition, Synergy issued 9.6 million shares of common stock as an inducement for Note holders to convert their Notes into Synergy common stock and recognized debt conversion expense of $25.6 million in the exchange.

In November 2016 Synergy exchanged $55.7 million in aggregate principal amount of the Notes, representing approximately 70% of the outstanding aggregate principal amount of Notes, for 20.5 million shares of Synergy's common stock, with a total of 17.9 million shares representing the conversion price of $3.11 pursuant to the existing terms of the Notes. The amortization of deferred debt costs was accelerated consistent with the 70% reduction of aggregate principal amount this transaction represented, and resulted in additional interest expense of approximately $2 million. The Company recognized debt conversion expense of $14.5 million representing 2.6 million shares in the exchange.

From January 1, 2016 through December 31, 2016, $135.5 million aggregate principal amount of the Notes was converted into approximately 56.6 million shares of Synergy common stock.

On May 5, 2016, Synergy announced that it had entered into definitive agreements with certain institutional investors to sell 29,948,334 shares of common stock at a price of $3.00 per share. The shares were offered and sold directly to institutional investors by the Company in a registered direct offering conducted without an underwriter or placement agent. The gross proceeds from the offering were approximately $89.8 million. The offering closed on May 6, 2016.

From January 1, 2016 through December 31, 2016 warrants to purchase 2,430,656 shares of common stock were exercised, yielding proceeds to us of $11.3 million.

On January 31, 2017, Synergy entered into an underwriting agreement with Cantor Fitzgerald & Co., as representative of several underwriters, to issue and sell 20,325,204 shares of common stock of the Company in an underwritten public

offering pursuant to a Registration Statement on Form S-3 and a related prospectus and prospectus

supplement, in each case filed with the Securities and Exchange Commission (the “Offering”). The public offering price was

$6.15 per share of Common Stock. The Offering closed on February 6, 2017, yielding net proceeds of approximately $121.6 million, after deducting underwriting discounts and commissions and offering expenses payable by the Company.

On June 27, 2017, Synergy increased the number of shares of common stock authorized for issuance from 350,000,000 to 400,000,000.

On November 13, 2017, Synergy entered into an underwriting agreement with Jefferies LLC, as representative of the several underwriters, to issue and sell 21,705,426 shares of common stock of the Company together with accompanying warrants (“Warrants”) to purchase an aggregate of 21,705,426 shares of Common Stock in an underwritten offering pursuant to a Registration Statement on Form S-3ASR and a related prospectus and prospectus supplement, in each case filed with the Securities and Exchange Commission (the “Offering”). The offering price was $2.58 per share of Common Stock and accompanying Warrant. Net proceeds from the Offering were approximately $52.2 million, after deducting underwriting discounts and commissions and offering expenses payable by the Company.