Revenue

Our revenues are primarily derived from the sale of rigid packaging products to customers. We recognize revenue at the amount we expect to be entitled to in exchange for promised goods for which we have transferred control to customers. If the consideration agreed to in a contract includes a variable amount, we estimate the amount of consideration we expect to be entitled to in exchange for transferring the promised goods to the customer. Generally, revenue is recognized at a point in time for standard promised goods at the time of shipment when title and risk of loss pass to the customer, and revenue is recognized over time in cases where we produce promised goods with no alternative use to us and for which we have an enforceable right of payment for production completed. The production cycle for customer contracts subject to over time recognition is generally completed in less than one month. We have elected to treat shipping and handling costs after the control of goods have been transferred to the customer as a fulfillment cost. Sales and similar taxes that are imposed on our sales and collected from customers are excluded from revenues.

The following tables present our revenues disaggregated by reportable business segment and geography as they best depict how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors.

Revenues by business segment for the three months ended March 31 were as follows:



	2018		2017
	(Dollars in thousands)
Metal containers	$	485,954	$	466,236
Closures	370,345		197,682
Plastics	155,981		141,489
	$	1,012,280	$	805,407

Revenues by geography for the three months ended March 31 were as follows:



	2018		2017
	(Dollars in thousands)
North America	$	779,790	$	674,839
Europe and other	232,490		130,568
	$	1,012,280	$	805,407

Our contracts generally include standard commercial payment terms generally acceptable in each region. We do not provide financing with extended payment terms beyond generally standard commercial payment terms for the applicable industry. We have no significant obligations for refunds, warranties or similar obligations.

Trade accounts receivable, net are shown separately on our Condensed Consolidated Balance Sheet. Contract assets are the result of the timing of revenue recognition, billings and cash collections. Our contract assets primarily consist of unbilled accounts receivable related to over time revenue recognition and were $73.6 million as of March 31, 2018. Unbilled receivables are included in trade accounts receivable, net on our Condensed Consolidated Balance Sheet. Had we not adopted the amended guidance for revenue recognition on January 1, 2018, our trade accounts receivable, net would have been $505.0 million and our inventories would have been $804.1 million as of March 31, 2018.