REVENUE

We recognize revenue as control of our products is transferred to our customers, which is generally at the time of shipment or upon delivery based on the contractual terms with our customers, or when services are completed. Control over certain of our custom-made window products transfers to our customers as production is completed, and revenue is recognized over the production period for these products, as our products do not have an alternative use and we have an enforceable right to payment during the production period. The production period of our custom-made window products generally does not lapse days, and for these products we currently recognize revenue based on the output of production, which is a faithful depiction of the transfer of these products to our customers. Our customers' payment terms generally range from 30 to 65 days of fulfilling our performance obligations and recognizing revenue.

We consider shipping and handling activities performed by us as activities to fulfill the sales of our products. Amounts billed for shipping and handling are included in net sales, while costs incurred for shipping and handling are included in cost of sales. We capitalize incremental costs of obtaining a contract and expense the costs on a straight-line basis over the contractual period if the cost is recoverable, the cost would not have been incurred without the contract and the term of the contract is greater than one year; otherwise, we expense the amounts as incurred. We do not adjust the promised amount of consideration for the effects of a financing component if the period between when we transfer our products or services and when our customers pay for our products or services is expected to be one year or less.

Our revenues are derived primarily from sales to customers in North America and Internationally, principally Europe. Net sales from these geographic markets, by segment, were as follows, in millions:



	Three Months Ended September 30, 2018
	Plumbing Products		Decorative Architectural Products		Cabinetry Products		Windows and Other Specialty Products		Total
Primary geographic markets:
North America	$	653	$	673	$	239	$	159	$	1,724
International, principally Europe	339		—		—		38		377
Total	$	992	$	673	$	239	$	197	$	2,101



	Nine Months Ended September 30, 2018
	Plumbing Products		Decorative Architectural Products		Cabinetry Products		Windows and Other Specialty Products		Total
Primary geographic markets:
North America	$	1,905	$	2,024	$	724	$	459	$	5,112
International, principally Europe	1,090		—		—		116		1,206
Total	$	2,995	$	2,024	$	724	$	575	$	6,318



	Three Months Ended September 30, 2017
	Plumbing Products		Decorative Architectural Products		Cabinetry Products		Windows and Other Specialty Products		Total
Primary geographic markets:
North America	$	599	$	562	$	216	$	161	$	1,538
International, principally Europe	351		—		13		43		407
Total	$	950	$	562	$	229	$	204	$	1,945

D. REVENUE (Concluded)



	Nine Months Ended September 30, 2017
	Plumbing Products		Decorative Architectural Products		Cabinetry Products		Windows and Other Specialty Products		Total
Primary geographic markets:
North America	$	1,761	$	1,719	$	673	$	465	$	4,618
International, principally Europe	1,010		—		38		123		1,171
Total	$	2,771	$	1,719	$	711	$	588	$	5,789

We provide customer programs and incentive offerings, including special pricing and co-operative advertising arrangements, promotions and other volume-based incentives. These customer programs and incentives are considered variable consideration. We include in revenue variable consideration only to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the variable consideration is resolved. This determination is made based upon known customer program and incentive offerings at the time of sale, and expected sales volume forecasts as it relates to our volume-based incentives. This determination is updated each reporting period. We recognized an increase to revenue of $2 million and $4 million for the three-month and nine-month periods ended September 30, 2018, respectively, and $4 million and $7 million for the three-month and nine-month periods ended September 30, 2017, respectively, of variable consideration related to performance obligations settled in previous periods.

Certain product sales include a right of return. We estimate future product returns at the time of sale based on historical experience and record a corresponding refund liability. We additionally record an asset, based on historical experience, for the amount of product we expect to return to inventory as a result of the return, which is recorded in prepaid expenses and other in the condensed consolidated balance sheets.

We record contract assets for items for which we have satisfied our performance obligation but our receipt of payment is contingent upon delivery or other circumstances other than the passage of time. Our contract assets are recorded in prepaid expenses and other in our condensed consolidated balance sheets. Our contract assets generally

become unconditional and are reclassified to receivables in the quarter subsequent to each balance sheet date. Our contract asset balance was $15 million and $11 million at September 30, 2018 and December 31, 2017, respectively.

We record contract liabilities primarily for deferred revenue. Our contract liabilities are recorded in accrued liabilities in our condensed consolidated balance sheets. Our contract liabilities are generally recognized to net sales in the immediately subsequent reporting period. Our contract liability balance was $18 million and $32 million at September 30, 2018 and December 31, 2017, respectively.