Revenue recognition

6 Months Ended

Jun. 30, 2020

Revenue from Contract with Customer [Abstract]

Revenue recognition

Revenue recognition

The Company operates as one operating segment. Therefore, results of its operations are reported on a consolidated basis for purposes of segment reporting, consistent with internal management reporting. The Company's revenues disaggregated by the major sources were as follows:

	Three Months Ended June 30, 2020						Three Months Ended June 30, 2019
	U.S. Government		Non-U.S. Government		Total		U.S. Government		Non-U.S. Government		Total
Product sales, net	$	224.2	$	74.3	$	298.5	$	94.6	$	88.9	$	183.5
Contract development and manufacturing services	44.6		28.0		72.6		—		18.7		18.7
Contracts and grants	20.7		2.9		23.6		38.3		2.7		41.0
Total revenues	$	289.5	$	105.2	$	394.7	$	132.9	$	110.3	$	243.2
	Six Months Ended June 30, 2020						Six Months Ended June 30, 2019
	U.S. Government		Non-U.S. Government		Total		U.S. Government		Non-U.S. Government		Total
Product sales, net	$	288.1	$	158.6	$	446.7	$	167.9	$	168.6	$	336.5
Contract development and manufacturing services	44.6		49.7		94.3		—		34.6		34.6
Contracts and grants	42.7		3.5		46.2		58.7		4.1		62.8
Total revenues	$	375.4	$	211.8	$	587.2	$	226.6	$	207.3	$	433.9

Contract liabilities

When performance obligations are not transferred to a customer at the end of a reporting period, cash received associated with amounts allocated to those performance obligations is reflected as contract liabilities on the consolidated balance sheets and is deferred until control of these performance obligations is transferred to the customer. The following table presents the rollforward of the contract liability balances:

December 31, 2019	$	88.9
Deferral of revenue	56.3
Revenue recognized	(27.2		)
June 30, 2020	$	118.0

Transaction price allocated to remaining performance obligations

During the three and six months ended June 30, 2020, the Company entered into a number of multi-year contract development and manufacturing services arrangements for the production of developmental vaccines. The Company's performance obligations associated with these arrangements include multiple performance obligations such as technology transfer activities, stand-ready obligations and drug substance manufacturing. The Company has determined that the technology transfer and stand-ready performance obligations are satisfied over time, while the drug substance manufacturing performance obligations are satisfied at a point in time when the goods have been released, legal title has passed and the goods are in the customer's possession.

As of June 30, 2020, the Company expects future revenues of approximately $1.4 billion associated with all performance obligations that have not been satisfied, including the new arrangements referenced in the previous paragraph. The Company expects to recognize a majority of these revenues within the next 24 months. However, the amount and timing of revenue recognition for unsatisfied performance obligations can materially change due to timing of funding appropriations from the USG and the overall success of the Company's development activities associated with its PHT procured product candidates that are then receiving development funding support from the USG under development contracts. In addition, the amount of future revenues associated with unsatisfied performance obligations excludes the value associated with unexercised option periods in the Company's contracts.

Contract assets

The Company considers unbilled accounts receivables and deferred costs associated with revenue generating contracts, which are not included in inventory or property, plant and equipment, as contract assets. As of June 30, 2020 and December 31, 2019, the Company had contract assets associated with deferred costs of $40.6 million and $34.0 million, respectively, which is reflected as a component of other assets on the Company's consolidated balance sheets.

Accounts receivable

Accounts receivable, including unbilled accounts receivable contract assets, consist of the following:

	June 30, 2020		December 31, 2019
Billed, net	$	202.2	$	227.3
Unbilled	56.4		43.4
Total, net	$	258.6	$	270.7

As of June 30, 2020 and December 31, 2019, allowances for doubtful accounts were $0.5 million and de minimis, respectively.