Revenue, Receivables and Contract Assets and Liabilities

Revenue

The following table disaggregates total revenue by timing of recognition (see Note 13 for disclosure of revenue by segment):



	Three Months Ended		Six Months Ended
In thousands	September 1, 2018		September 1, 2018
Recognized at shipment	$	166,534	$	323,401
Recognized over time	195,599		375,263
Total	$	362,133	$	698,664

Receivables

Trade and construction accounts receivable consist of amounts billed and due from customers. The amounts due are stated at their estimated net realizable value. We maintain an allowance for doubtful accounts to provide for the estimated amount of receivables that will not be collected. This allowance is based on an assessment of customer creditworthiness, historical payment experience and the age of outstanding receivables. Retainage on construction contracts represents amounts withheld by our customers on long-term projects until the project reaches a level of completion where amounts are released.



In thousands	September 1, 2018			March 3, 2018
Trade accounts	$	153,220		$	157,562
Construction contracts	17,462			26,545
Construction contracts - retainage	31,819			26,388
Other receivables	—			2,887
Total receivables	202,501			213,382
Less: allowance for doubtful accounts	(1,731		)	(1,530		)
Net receivables	$	200,770		$	211,852

Contract assets and liabilities

Contract assets consist of retainage, costs and earnings in excess of billings and other unbilled amounts typically generated when revenue recognized exceeds the amount billed to the customer. Contract liabilities consist of billings in excess of costs and earnings and other deferred revenue on contracts. Retainage is classified within receivables and deferred revenue is classified within other current liabilities on our consolidated balance sheets.

The time period between when performance obligations are complete and when payment is due is not significant. In certain of our businesses that recognize revenue over time, progress billings follow an agreed-upon schedule of values, and retainage is withheld by the customer until the project reaches a level of completion where amounts are released.



In thousands	September 1, 2018		March 3, 2018
Contract assets	$	76,404	$	30,508
Contract liabilities	31,623		20,120

The increase in contract assets was due to additional businesses recognizing revenue in advance of billings, as a result of changing accounting policies for revenue recognition upon adoption of ASC 606. The increase in contract liabilities was due to timing of project activity within our businesses that operate under long-term contracts.

In the first six months of fiscal 2019, we recognized revenue of $10.4 million related to contract liabilities at March 4, 2018, and revenue of $3.8 million related to performance obligations satisfied in previous periods due to changes in contract estimates. For the second quarter of fiscal 2019, we recognized revenue of $1.3 million related to contract liabilities at March 4, 2018, and revenue of $1.5 million related to performance obligations satisfied in previous periods due to changes in contract estimates.

Some of our contracts have an expected duration of longer than a year, with performance obligations extending over that timeframe. Generally these contracts are in our businesses with long-term contracts which recognize revenue over time. As of September 1, 2018, the transaction price associated with unsatisfied performance obligations was approximately $695.1 million. The performance obligations are expected to be satisfied, and the corresponding revenue to be recognized, over the following estimated time periods:



In thousands	September 1, 2018
Within one year	$	462,097
Within two years	222,677
Beyond	10,313
Total	$	695,087