XML 81 R44.htm IDEA: XBRL DOCUMENT
v3.20.4

Note 8 - Stock-based Compensation - Number of Stock Option Awards Exercisable and their Weighted Average Exercise Price (Details) | 12 Months Ended
--- | ---
Dec. 31, 2020 $ / shares shares
Upper Exercise Price Range (in dollars per share) | $ 18
Outstanding Number (in shares) | shares | 29,056
Outstanding Weighted Average Remaining Life (Year) | 7 years 6 months
Outstanding Weighted Average Exercise Price (in dollars per share) | $ 6.14
Exercisable Number (in shares) | shares | 13,036
Exercisable Weighted Average Exercise Price (in dollars per share) | $ 3.27
Exercise Price Range 01 [Member] |
Upper Exercise Price Range (in dollars per share) | $ 3
Outstanding Number (in shares) | shares | 2,514
Outstanding Weighted Average Remaining Life (Year) | 6 years 1 month 6 days
Outstanding Weighted Average Exercise Price (in dollars per share) | $ 2.19
Exercisable Number (in shares) | shares | 1,414
Exercisable Weighted Average Exercise Price (in dollars per share) | $ 1.25
Exercise Price Range 02 [Member] |
Upper Exercise Price Range (in dollars per share) | $ 6
Outstanding Number (in shares) | shares | 12,689
Outstanding Weighted Average Remaining Life (Year) | 7 years
Outstanding Weighted Average Exercise Price (in dollars per share) | $ 4.22
Exercisable Number (in shares) | shares | 6,854
Exercisable Weighted Average Exercise Price (in dollars per share) | $ 2.48
Exercise Price Range 03 [Member] |
Upper Exercise Price Range (in dollars per share) | $ 9
Outstanding Number (in shares) | shares | 10,852
Outstanding Weighted Average Remaining Life (Year) | 9 years 2 months 12 days
Outstanding Weighted Average Exercise Price (in dollars per share) | $ 7.88
Exercisable Number (in shares) | shares | 2,005
Exercisable Weighted Average Exercise Price (in dollars per share) | $ 4.89
Exercise Price Range 04 [Member] |
Upper Exercise Price Range (in dollars per share) | $ 12
Outstanding Number (in shares) | shares | 2,347
Outstanding Weighted Average Remaining Life (Year) | 4 years 6 months
Outstanding Weighted Average Exercise Price (in dollars per share) | $ 10.85
Exercisable Number (in shares) | shares | 2,129
Exercisable Weighted Average Exercise Price (in dollars per share) | $ 4.51
Exercise Price Range 05 [Member] |
Upper Exercise Price Range (in dollars per share) | $ 15
Outstanding Number (in shares) | shares | 559
Outstanding Weighted Average Remaining Life (Year) | 4 years 1 month 6 days
Outstanding Weighted Average Exercise Price (in dollars per share) | $ 12.30
Exercisable Number (in shares) | shares | 539
Exercisable Weighted Average Exercise Price (in dollars per share) | $ 6.43
Exercise Price Range 06 [Member] |
Upper Exercise Price Range (in dollars per share) | $ 18
Outstanding Number (in shares) | shares | 95
Outstanding Weighted Average Remaining Life (Year) | 4 years 6 months
Outstanding Weighted Average Exercise Price (in dollars per share) | $ 15.39
Exercisable Number (in shares) | shares | 95
Exercisable Weighted Average Exercise Price (in dollars per share) | $ 10.57

X
- Definition The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageRemainingContractualTerm2
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=bcrx_ExercisePriceRange01Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=bcrx_ExercisePriceRange02Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=bcrx_ExercisePriceRange03Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=bcrx_ExercisePriceRange04Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=bcrx_ExercisePriceRange05Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=bcrx_ExercisePriceRange06Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |