CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - Convertible debt $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Convertible Senior Notes, 2.5%
Reacquisition of equity component, tax loss (benefit)	$ 1,445
Convertible Senior Notes, 5.0%
Reacquisition of equity component, tax loss (benefit)	$ (7,212)

Adjustments To Additional Paid In Capital, Equity Component Of Convertible Debt, Tax Expense (Benefit)

No definition available.

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Namespace Prefix:	asrt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration