Revenue

Our primary product lines are Infusion Consumables, IV Solutions, Infusion Systems and Critical Care. The vast majority of our sales of these products are made on a stand-alone basis to hospitals and distributors. Revenue is typically recognized upon transfer of control of the products, which we deem to be at point of shipment.

For certain Infusion Systems agreements, our customers are provided the right to use our systems hardware upon entering into agreements to purchase specified amounts of consumables. Revenues from these agreements are presented in product revenue on our condensed consolidated statements of operation.

Payment is typically due in full within 30 days of delivery or the start of the contract term. Revenue is recorded in an amount that reflects the consideration we expect to be entitled to in exchange for those goods or services. We offer certain volume-based rebates to our distribution customers, which we record as variable consideration when calculating the transaction price. Rebates are offered on both a fixed and tiered/variable basis. In both cases, we use information available at the time and our historical experience with each customer to estimate the most likely rebate amount.

We also warrant products against defects and have a policy permitting the return of defective products, for which we accrue and expense at the time of sale using information available and our historical experience. We also provide for extended service-type warranties, which we consider to be separate performance obligations. We allocate a portion of the transaction price to the extended service-type warranty based on its estimated relative selling price, and recognize revenue over the period the warranty service is provided.

Revenue disaggregated

The following table represents our revenues disaggregated by geography (in thousands):



	For the three months ended March 31,
Geography	2019		2018
Europe, the Middle East and Africa	$	32,378	$	39,524
Other Foreign	51,361		50,932
Total Foreign	83,739		90,456
United States	247,193		281,577
Total Revenues	$	330,932	$	372,033

The following table represents our revenues disaggregated by product (in thousands):



	For the three months ended March 31,
Product line	2019		2018
Infusion Consumables	$	120,580	$	119,911
IV Solutions	113,182		144,440
Infusion Systems ⁽¹⁾	84,282		93,439
Critical Care	12,888		14,234
Total Revenues	$	330,932	$	372,033

Contract balances

The following table presents our changes in the contract balances for the three months ended March 31, 2019 and 2018 (in thousands):



	Contract Liabilities
Beginning balance, January 1, 2019	$	(4,282	)
Equipment revenue recognized	448
Equipment revenue deferred due to implementation	(1,343		)
Software revenue recognized	345
Software revenue deferred due to implementation	(1,593		)
Ending balance, March 31, 2019	$	(6,425	)

Beginning balance, January 1, 2018	$	(7,066	)
Equipment revenue recognized	288
Equipment revenue deferred due to implementation	(1,558		)
Software revenue recognized	655
Software revenue deferred due to implementation	(4,080		)
Ending balance, March 31, 2018	$	(11,761	)

As of March 31, 2019, revenue from remaining performance obligations related to implementation of software and equipment is $4.9 million. We expect to recognize substantially all of this revenue within the next three months. Revenue from remaining performance obligations related to annual software licenses is $1.5 million. We expect to recognize substantially all of this revenue over the next twelve months.