Organization and Basis of Presentation - Liquidity (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Organization and Basis of Presentation
Cash equivalents and short-term investments, Fair Value	$ 204,841	$ 247,512

Cash, cash equivalents and short term investments fair value disclosure.

No definition available.

Name:	ardx_CashCashEquivalentsAndShortTermInvestmentsFairValueDisclosure
Namespace Prefix:	ardx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant