Carrying Value and Fair Value of Certain Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (Fair Value, Measurements, Recurring [Member], USD $) | Sep. 30, 2014 | Dec. 31, 2013 |
In Thousands, unless otherwise specified |
Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash and cash equivalents | $116,684 | $139,318 |
Restricted marketable securities | ' | 5 |
Available-for-sale securities | 3 | 15 |
Warrant participations | 0 | 0 |
Total marketable securities | 49,057 | 44,338 |
Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash and cash equivalents | 0 | 0 |
Restricted marketable securities | ' | 0 |
Available-for-sale securities | 0 | 0 |
Warrant participations | 0 | 0 |
Total marketable securities | 0 | 0 |
Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash and cash equivalents | 0 | 0 |
Restricted marketable securities | ' | 0 |
Available-for-sale securities | 0 | 0 |
Warrant participations | 71 | 1,563 |
Total marketable securities | 0 | 0 |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash and cash equivalents | 116,684 | 139,318 |
Restricted marketable securities | ' | 5 |
Available-for-sale securities | 3 | 15 |
Warrant participations | 71 | 1,563 |
Total marketable securities | 49,057 | 44,338 |
NuPathe [Member] | Common stock [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Ownership interest | ' | 16,874 |
NuPathe [Member] | Common stock [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Ownership interest | ' | 0 |
NuPathe [Member] | Common stock [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Ownership interest | ' | 0 |
NuPathe [Member] | Common stock [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Ownership interest | ' | 16,874 |
NuPathe [Member] | Warrants and options [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Ownership interest | ' | 0 |
NuPathe [Member] | Warrants and options [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Ownership interest | ' | 0 |
NuPathe [Member] | Warrants and options [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Ownership interest | ' | 3,183 |
NuPathe [Member] | Warrants and options [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Ownership interest | ' | 3,183 |
Commercial paper [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 6,592 | 13,599 |
Commercial paper [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 0 | 0 |
Commercial paper [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 0 | 0 |
Commercial paper [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 6,592 | 13,599 |
U.S. Treasury Bills [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 1,504 | 8,014 |
U.S. Treasury Bills [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 0 | 0 |
U.S. Treasury Bills [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 0 | 0 |
U.S. Treasury Bills [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 1,504 | 8,014 |
Government agency bonds [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 13,503 | 9,945 |
Government agency bonds [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 0 | 0 |
Government agency bonds [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 0 | 0 |
Government agency bonds [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 13,503 | 9,945 |
Certificates of deposit [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 27,458 | 12,780 |
Certificates of deposit [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 0 | 0 |
Certificates of deposit [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | 0 | 0 |
Certificates of deposit [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Total marketable securities | $27,458 | $12,780 |