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Debt - Debt from Royalty-Bearing Instrument-December 2012 Financing - Additional Information (Detail) - USD ($) |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Dec. 06, 2012 | Nov. 30, 2020 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Debt Disclosure [Line Items] |  |  |  |  |
Outstanding debt |  |  | $ 0 | $ 50,130,000 |
Interest expense, non-cash |  |  | 635,000 | 1,644,000 | $ 2,183,000
CPPIB |  |  |  |  |
Debt Disclosure [Line Items] |  |  |  |  |
Repayment of debt |  |  | 150,000,000.0 |  |
Repayment under agreement |  | $ 9,600,000 | 52,400,000 |  |
BioPharma Debt |  |  |  |  |
Debt Disclosure [Line Items] |  |  |  |  |
Amount received at the closing of the agreement | $ 100,000,000.0 |  |  |  |
Maximum repayment of future revenue and receivables | $ 150,000,000.0 |  |  |  |
Royalty-Bearing Debt | Cash |  |  |  |  |
Debt Disclosure [Line Items] |  |  |  |  |
Interest expense, contractual coupon interest |  |  | 1,600,000 | 4,400,000 |
Royalty-Bearing Debt | Non Cash |  |  |  |  |
Debt Disclosure [Line Items] |  |  |  |  |
Interest expense, non-cash |  |  | $ 600,000 | $ 1,600,000 |

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- Definition Amount of amortization expense attributable to debt discount (premium) and debt issuance costs. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28555-108399 + Details
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- Definition Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph 8 -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 + Details
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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + 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 210.5-02.19,20) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions. + References No definition available. + Details
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- Definition The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585 + Details
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