Number of interest and principal payments.

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- Definition

Number of interest only installments.

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No definition available.

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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

Amount of the fee that accompanies borrowing money under the debt instrument.

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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 210.5-02.22(b))
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Gross amount of debt extinguished.

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No definition available.

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- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash outflow for incremental, external costs directly pertaining to an early extinguishment of debt, including legal costs and prepayment penalties, and excluding interest and repayment of debt principal.

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No definition available.

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- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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- Definition

Number of shares issued during the period as a result of the conversion of convertible securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Debt and Related Warrants - 2015 Facility - Additional Information (Details)	1 Months Ended				12 Months Ended
	Jan. 31, 2016 USD ($)	Jun. 30, 2015 USD ($) installment payment shares	Feb. 28, 2014 USD ($) shares	Dec. 31, 2010 USD ($)	Dec. 31, 2016 shares	Oct. 07, 2016 shares
2015 Credit Facility \| Warrants to Purchase Series B Redeemable Convertible Preferred Stock
Debt
Number of shares the warrant can be converted to \| shares		18,461
Term Loan 2015 Credit Facility
Debt
Loan agreement amount		$ 8,000,000
Interest rate		8.75%
Line of credit facility expiration period		4 years
Number of term loan installments \| installment		15
Number of interest and principal Payments \| payment		33
Term loan end-of-term fee		$ 180,000
Term Loan 2015 Credit Facility \| LIBOR
Debt
Interest rate, basis spread percentage		7.75%
Term Loan 2015 Credit Facility \| Prime Rate
Debt
Interest rate, basis spread percentage		3.75%
Revolving loan 2015 Credit Facility
Debt
Loan agreement amount		$ 4,000,000
Line of credit facility expiration period		2 years
Proceeds from revolving loan	$ 1,500,000
SVB Credit Facility
Debt
Repayment of credit facility		$ 2,800,000
Unamortized debt discount		114,000
Prepayment penalty		$ 20,000
SVB Credit Facility \| Warrants to Purchase Series B Redeemable Convertible Preferred Stock
Debt
Number of shares the warrant can be converted to \| shares			6,153
Term Loan SVB Credit Facility
Debt
Loan agreement amount			$ 4,000,000	$ 2,000,000
Agreement term				4 years
Interest rate			5.00%
Line of credit facility expiration period			4 years
Term Loan SVB Credit Facility \| Prime Rate
Debt
Interest rate, basis spread percentage			3.75%
Revolving Loan SVB Credit Facility
Debt
Loan agreement amount			$ 4,000,000	$ 2,000,000
Agreement term				2 years
Interest rate			5.00%
Line of credit facility expiration period			2 years
Revolving Loan SVB Credit Facility \| Prime Rate
Debt
Interest rate, basis spread percentage			1.75%
Common Stock
Debt
Conversion of convertible securities \| shares					2,486,199
Common Stock \| 2015 Credit Facility \| Warrants to Purchase Series B Redeemable Convertible Preferred Stock
Debt
Conversion of convertible securities \| shares		18,461
Common Stock \| SVB Credit Facility \| Warrants to Purchase Series B Redeemable Convertible Preferred Stock
Debt
Number of shares the warrant can be converted to \| shares						6,153