Revenues

9 Months Ended

Sep. 30, 2019

Revenue from Contract with Customer [Abstract]

Revenue Recognition

Revenues are recognized when control of the promised goods or services is transferred to our customers, in an amount that reflects the consideration we expect to be entitled to in exchange for those goods or services. The majority of our revenues are recognized over time as services are performed, with certain revenues, most significantly the revenue share we earn from our print textbook partners, being recognized at the point in time when print textbooks are shipped to students.

The following tables set forth our total net revenues for the periods shown disaggregated for our Chegg Services and Required Materials product lines (in thousands, except percentages):



	Three Months Ended September 30,				Change
	2019		2018		$		%
Chegg Services	$	69,304	$	54,201	$	15,103	28	%
Required Materials	24,847		20,036		4,811		24
Total net revenues	$	94,151	$	74,237	$	19,914	27



	Nine Months Ended September 30,				Change
	2019		2018		$		%
Chegg Services	$	224,903	$	172,327	$	52,576	31	%
Required Materials	60,519		53,081		7,438		14
Total net revenues	$	285,422	$	225,408	$	60,014	27

During the three months ended September 30, 2019, we recognized $15.7 million of revenues that were included in our deferred revenue balance as of June 30, 2019. During the nine months ended September 30, 2019, we recognized $16.0 million of revenues that were included in our deferred revenue balance as of December 31, 2018. During the three and nine months ended September 30, 2019, we recognized $2.2 million and $2.7 million, respectively, of previously deferred revenues recognized from performance obligations satisfied in previous periods related to variable consideration recognized from our agreement with our Required Materials print textbook partner. The aggregate amount of unsatisfied performance obligations is approximately $29.0 million as of September 30, 2019, of which substantially all is expected to be recognized into revenues over the next year and the remainder within two years.

Contract Balances

The following table presents our accounts receivable, net and deferred revenue balances (in thousands, except percentages):



					Change
	September 30, 2019		December 31, 2018		$		%
Accounts receivable, net	$	13,678	$	12,733	$	945	7	%
Deferred revenue	$	27,457	$	17,418	$	10,039	58	%

During the nine months ended September 30, 2019, our accounts receivable, net balance increased by $0.9 million, or 7%, primarily due to timing of billings partially offset by an improvement in cash collections. During the nine months ended September 30, 2019, our deferred revenue balance increased by $10.0 million, or 58%, primarily due to increased bookings for our Chegg Study service and eTextbook rentals driven by the seasonality of our business. We had no contract assets as of September 30, 2019 and an immaterial amount as of December 31, 2018.