STOCK-BASED COMPENSATION AND STOCK PLANS (Detail Textuals 2) (Restricted Stock, USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of restricted stock vested	$ 203	$ 749

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

No definition available.

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Namespace Prefix:	arql_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration