ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Basis of Presentation and Liquidity (Details) $ in Millions	Jun. 30, 2025 USD ($)
ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Cash, cash equivalents and short-term investments	$ 108.4

Amount of cash, cash equivalents and short-term investments excluding restricted cash.

No definition available.

Name:	rigl_CashCashEquivalentsAndShortTermInvestmentsExcludingRestrictedCash
Namespace Prefix:	rigl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant