Revenue Recognition

6 Months Ended

Jun. 30, 2019

Revenue from Contract with Customer [Abstract]

The following table disaggregates revenues by type within each of our business segments:



	Three Months Ended June 30,				Six Months Ended June 30,
	2019		2018		2019		2018
Gaming
Gaming operations	$	150	$	160	$	302	$	321
Gaming machine sales	148		168		284		313
Gaming systems	67		84		141		159
Table products	62		59		122		121
Total	$	427	$	471	$	849	$	914

Lottery
Instant products	$	150	$	150	$	290	$	300
Lottery systems	81		57		168		109
Total	$	231	$	207	$	458	$	409

SciPlay
Mobile	$	98	$	77	$	195	$	149
Web and other	20		23		41		48
Total	$	118	$	100	$	236	$	197

Digital
Sports and platform	$	26	$	20	$	56	$	46
Gaming and other	43		47		83		91
Total	$	69	$	67	$	139	$	137

The amount of rental income revenue that is outside the scope of ASC 606 was $95 million and $191 million for the three and six months ended June 30, 2019, respectively, and $69 million and $136 million for the three and six months ended June 30, 2018, respectively.

Contract Liabilities and Other Disclosures

The following table summarizes the activity in our contract liabilities for the reporting period:



	Six Months Ended June 30,
	2019
Contract liability balance, beginning of period⁽¹⁾	$	97
Liabilities recognized during the period	33
Amounts recognized in revenue from beginning balance	(30		)
Contract liability balance, end of period⁽¹⁾	$	100
(1) Contract liabilities are included within Accrued liabilities and Other long-term liabilities in our June 30, 2019 consolidated balance sheet.

The timing of revenue recognition, billings and cash collections results in billed receivables, unbilled receivables (contract assets), and customer advances and deposits (contract liabilities) on our consolidated balance sheets. Other than contracts with customers with financing arrangements exceeding 12 months, revenue recognition is generally proximal to conversion to cash, except for Lottery instant products sold under POS contracts. Revenue is recognized for such contracts upon delivery to our customers, while conversion to cash is based on the retail sale of the underlying ticket to end consumers. As a result, for such contracts revenue recognition under ASC 606 does not approximate conversion to cash. Total revenue recognized under such contracts for the three and six months ended June 30, 2019 was $26 million and $49 million, respectively, and was $24 million and $58 million for the three and six months ended June 30, 2018, respectively. The following table summarizes our receivables and contract asset balances for the periods indicated (other than contract liabilities disclosed above):



	Receivables		Contract Assets⁽¹⁾
Beginning of period balance	$	753	$	114
End of period balance, June 30, 2019	778		114
(1) Contract assets are included primarily within Prepaid expenses, deposits and other current assets in our June 30, 2019 consolidated balance sheet.

As of June 30, 2019, we did not have material unsatisfied performance obligations for contracts expected to be long-term or contracts for which we recognize revenue at an amount other than for which we have the right to invoice for goods or services delivered or performed.