Revenue Recognition (Tables)

3 Months Ended

Mar. 31, 2020

Revenue from Contract with Customer [Abstract]

Disaggregated Revenues by Timing of Transfer of Goods or Services

The following tables present our revenues disaggregated by timing of transfer of goods or services (in thousands):

	Three Months Ended March 31, 2020
	Product Revenue, net		Collaboration and License Revenue		Total
Timing of revenue recognition:
Transferred at a point in time	$	25,637	$	—	$	25,637
Transferred over time	—		752		752
Total	$	25,637	$	752	$	26,389

	Three Months Ended March 31, 2019
	Product Revenue, net		Collaboration and License Revenue		Total
Timing of revenue recognition:
Transferred at a point in time	$	20,362	$	—	$	20,362
Transferred over time	—		1,807		1,807
Total	$	20,362	$	1,807	$	22,169

Schedule of Net Product Revenues Disaggregated by Geographic Region

The following table presents our net product revenues disaggregated by geographic region (in thousands):

	Three Months Ended March 31,
	2020		2019
United States	$	23,055	$	20,362
Europe	2,582		—
Total revenues	$	25,637	$	20,362

Activity of Product Revenue Reserves

The activities and ending reserve balances for each significant category of product revenue reserves (which constitute variable considerations) were as follows (in thousands):

	Return			Chargebacks			Other			Total
Balance at December 31, 2019	$	7,561		$	899		$	2,661		$	11,121
Provision related to sales made in:
Current periods	2,720			1,338			1,100			5,158
Payments and customer credits issued	(1,121		)	(1,483		)	(1,712		)	(4,316		)
Balance at March 31, 2020	$	9,160		$	754		$	2,049		$	11,963

Schedule of Changes in Contract Assets and Liabilities

The following table presents changes in our contract assets and liabilities for the three months ended March 31, 2020 (in thousands):

	Balance at Beginning of Period		Addition		Deduction			Balance at End of Period
Contract assets:
Unbilled - collaboration and license revenue	$	3,783	$	366	$	(741	)	$	3,408
Total contract assets	$	3,783	$	366	$	(741	)	$	3,408
Contract liabilities:
Deferred revenue	$	5,518	$	—	$	(622	)	$	4,896
Total contract liabilities	$	5,518	$	—	$	(622	)	$	4,896

Significant changes in the contract liabilities balances during the period are as follows (in thousands):

	Three Months Ended as of March 31, 2020
Revenue recognized according to the current period performance that was included in the contract liability at the beginning of the period	$	314

Estimated Revenue Expected to be Recognized in Future Related to Performance Obligations

The following table includes estimated revenue expected to be recognized in the future, related to performance obligations that are unsatisfied or partially unsatisfied as of March 31, 2020 (in thousands):

Collaborator	Transaction Price Allocated to the Remaining Performance Obligation as of March 31, 2020		Expected Year By Which Revenue Recognition Will Be Completed	Percentage of Revenue Recognized
BMS and Pfizer - 2016 agreement	$	382	2021	97	%
Daiichi Sankyo - 2014 agreement	600		2021	98	%
Daiichi Sankyo - 2016 agreement	1,969		2025	88	%
Bayer - 2016 agreement	1,472		2025	91	%
Total	$	4,423