Summary Results of Regulus Balance Sheet (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Balance Sheet Data:
Cash, cash equivalents and marketable securities	$ 38,144
Current assets	38,666
Total assets	42,881
Current liabilities	12,850
Non-current liabilities	28,834
Notes payable	11,259
Net assets	$ 1,197

The amount of assets reported by an equity method investment of the entity.

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 7: http://www.xbrl.org/2003/role/presentationRef

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+ Details

- Definition

The amount of current assets reported by an equity method investment of the entity.

+ References

+ Details

- Definition

The amount of current liabilities reported by an equity method investment of the entity.

+ References

+ Details

- Definition

The amount of noncurrent liabilities reported by an equity method investment of the entity.

+ References

+ Details