Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

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The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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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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Date the original debt was scheduled to mature, in CCYY-MM-DD format.

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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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The price per share of the conversion feature embedded in the debt instrument.

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

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The effective interest rate during the reporting period.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Convertible Loans - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			9 Months Ended
	Jan. 29, 2016	Oct. 26, 2015	Sep. 30, 2017	Sep. 30, 2016
Debt Conversion [Line Items]
Borrowings under loan agreement				$ 35,000
Conversion of convertible loans to Series B Preferred Shares				61,929
Gain on extinguishment of debt				$ 11,482
Vertex Convertible Loans [Member]
Debt Conversion [Line Items]
Borrowings under loan agreement		$ 38,200
Loan, accrued interest rate		2.50%
Loan agreement maturity date			Apr. 26, 2016
Vertex Convertible Loans [Member] \| Series B Redeemable Convertible Preferred Shares [Member]
Debt Conversion [Line Items]
Preferred shares, shares issued upon conversion	2,859,278
Preferred shares, conversion price per share	$ 13.43
Fair value of convertible loan	$ 26,900
Gain on extinguishment of debt	11,500
Bayer Convertible Loans [Member]
Debt Conversion [Line Items]
Loan agreement maturity date			Jan. 29, 2016
Borrowings under loan agreement	$ 35,000
Loan, accrued interest rate	2.00%
Borrowings under loan agreement	$ 35,000
Bayer Convertible Loans [Member] \| Series B Redeemable Convertible Preferred Shares [Member]
Debt Conversion [Line Items]
Preferred shares, shares issued upon conversion	2,605,330
Preferred shares, conversion price per share	$ 13.43
Fair value of convertible loan	$ 24,500
Allocated to convertible loan	27,000
Interest expense	8,000
Conversion of convertible loans to Series B Preferred Shares	$ 35,000