XML 32 R20.htm IDEA: XBRL DOCUMENT v3.21.1

Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2021

Share-based Payment Arrangement [Abstract]

Stock-Based Compensation Expense

The following stock-based compensation expense was recognized for the periods indicated (in thousands):

			Three Months Ended March 31,
			2021						2020
Research and development			$	2,727					$	2,434
Selling, general and administrative			2,559						2,057
Total stock-based compensation expense			$	5,286					$	4,491

Valuation Assumptions Using the Black-Scholes Option-Pricing Model

The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model using the assumptions in the following table for options issued during the period indicated:

			Three Months Ended March 31,
			2021						2020
Expected dividend yield			0%						0%
Expected volatility			86.4% -86.7%						67.3% - 69.5%
Risk-free interest rate			0.6% - 1.4%						0.6% - 1.8%
Expected term			6.25 years						6.25 years

Stock Option and Restricted Stock Unit Activity

The following table summarizes stock option activity during the three months ended March 31, 2021:

			Shares						Weighted- Average Exercise Price						Weighted-Average Remaining Contractual Term (Years)						Aggregate Intrinsic Value  (in thousands)
Outstanding, December 31, 2020			7,258,353						$	21.48					6.8
Granted			1,555,796						19.52
Exercised			(144,249)						17.59
Forfeited or expired			(66,463)						17.98
Outstanding, March 31, 2021			8,603,437						21.21						7.2						$	91,820
As of March 31, 2021:
Exercisable			4,825,295						22.96						5.7						43,209
Vested and expected to vest			8,167,732						21.32						7.1						86,309

Schedule of RSU Activity

The following table summarizes RSU activity during the three months ended March 31, 2021:

			Shares						Weighted-Average Grant Date Fair Value
Outstanding, December 31, 2020			209,250						$	15.92
Granted			—						—
Exercised			—						—
Forfeited or expired			(5,150)						15.32
Outstanding, March 31, 2021			204,100						15.93

X

- References

No definition available.

+ Details

Name:	mgnx_ScheduleOfShareBasedCompensationStockOptionsAndRestrictedStockUnitsActivityTableTextBlock
Namespace Prefix:	mgnx_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of allocation of amount expensed and capitalized for award under share-based payment arrangement to statement of income or comprehensive income and statement of financial position. Includes, but is not limited to, corresponding line item in financial statement.

+ 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 (h)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901

+ Details

Name:	us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions.

+ 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 (f)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

Name:	us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Disclosure of the number and weighted-average grant date fair value for restricted stock and restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock and restricted stock units that were granted, vested, or forfeited during the year.

+ References

No definition available.

+ Details

Name:	us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration