v3.10.0.1

Stockholders' Deficit - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jan. 01, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders’ deficit	$ 54,219		$ 54,219			$ 14,095
Increase in stockholders' deficit			(40,100)
Net loss	16,995	$ 23,498	60,409	$ 133,011
Proceeds related to issuance of stock-based compensation and sock option exercises			12,500
Additional debt discount			6,228	$ 0
Adjustment to accumulated deficit	$ 1,058,331		$ 1,058,331			$ 998,538
Difference between Revenue Guidance in Effect before and after Topic 606 \| Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustment to accumulated deficit					$ 600

Convertible Debt, Unrealized Gain (Loss), Change In Conversion Fair Value

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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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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Amount of cash inflow from issuance of shares under share-based compensation arrangement. Issuance includes, but is not limited to, exercise of stock options and similar instruments.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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KERYX BIOPHARMACEUTICALS INC 10-Q