The value of a block of common stock purchased that will be matched.

No definition available.

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- Definition

The maximum value of common stock purchased that will be matched.

+ References

No definition available.

+ Details

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- Definition

The maximum grant date value of the RSUs issued for each block of common stock purchased per the agreement.

+ References

No definition available.

+ Details

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

- Definition

Face amount per share of no-par value common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Period Type:	instant

- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- 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.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

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Data Type:	num:perShareItemType
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- Details

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- Details

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Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
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STOCK-BASED COMPENSATION - Equity Match Program (Details) - USD ($)		12 Months Ended
	Dec. 06, 2017	Dec. 31, 2018	Dec. 31, 2017
Stock-based compensation
Par value (in dollars per share)		$ 0.0001	$ 0
Common stock issued (in shares)		64,185,224	63,400,348
CEO \| Equity Match Program
Stock-based compensation
Par value (in dollars per share)	$ 0
Block of common stock purchased value	$ 100,000
Maximum amount of common stock purchased	600,000
Common stock issued (in shares)		75,000
Average price per share (in dollars per share)		$ 8.16
CEO \| Restricted stock units \| Equity Match Program
Stock-based compensation
Maximum grant date value of RSU	$ 100,000
Vesting period, anniversary of the first day during the purchase period	3 years
Number of units awarded (in shares)		73,529
Fair value of units awarded at grant date (in dollars per share)		$ 8.16