The following tables present the Company’s net revenues disaggregated by geography based on the location of the customer, by product line (in thousands):


	Three Months Ended June 30, 2021

	Brick Products		Advanced Products		Total

United States	$	19,708	$	14,356	$	34,064
Europe		10,224		1,285		11,509
Asia Pacific		24,045		25,339		49,384
All other		375		44		419

	$	54,352	$	41,024	$	95,376


	Six Months Ended June 30, 2021

	Brick Products		Advanced Products		Total

United States	$	38,291	$	22,905	$	61,196
Europe		18,420		2,280		20,700
Asia Pacific		51,373		49,992		101,365
All other		727		184		911

	$	108,811	$	75,361	$	184,172


	Three Months Ended June 30, 2020

	Brick Products		Advanced Products		Total

United States	$	15,005	$	5,217	$	20,222
Europe		9,427		2,289		11,716
Asia Pacific		21,383		16,774		38,157
All other		613		53		666

	$	46,428	$	24,333	$	70,761


	Six Months Ended June 30, 2020

	Brick Products		Advanced Products		Total

United States	$	40,975	$	12,814	$	53,789
Europe		13,995		3,168		17,163
Asia Pacific		35,039		26,150		61,189
All other		1,936		85		2,021

	$	91,945	$	42,217	$	134,162

The following tables present the Company’s net revenues disaggregated by the category of revenue, by product line (in thousands):


	Three Months Ended June 30, 2021

	Brick Products		Advanced Products		Total

Direct customers, contract manufacturers and non-stocking distributors	$	37,614	$	32,644	$	70,258
Stocking distributors, net of sales allowances		16,634		4,634		21,268
Non-recurring engineering		104		3,726		3,830
Royalties		—		3		3
Other		—		17		17

	$	54,352	$	41,024	$	95,376


	Six Months Ended June 30, 2021

	Brick Products		Advanced Products		Total

Direct customers, contract manufacturers and non-stocking distributors	$	81,422	$	61,701	$	143,123
Stocking distributors, net of sales allowances		27,181		8,772		35,953
Non-recurring engineering		208		4,797		5,005
Royalties		—		56		56
Other		—		35		35

	$	108,811	$	75,361	$	184,172


	Three Months Ended June 30, 2020

	Brick Products		Advanced Products		Total

Direct customers, contract manufacturers and non-stocking distributors	$	39,472	$	20,044	$	59,516
Stocking distributors, net of sales allowances		6,814		1,576		8,390
Non-recurring engineering		142		2,695		2,837
Other		—		18		18

	$	46,428	$	24,333	$	70,761


	Six Months Ended June 30, 2020

	Brick Products		Advanced Products		Total

Direct customers, contract manufacturers and non-stocking distributors	$	75,211	$	34,811	$	110,022
Stocking distributors, net of sales allowances		16,436		4,638		21,074
Non-recurring engineering		298		2,732		3,030
Other		—		36		36

	$	91,945	$	42,217	$	134,162

The following table presents the changes in certain contract assets and (liabilities) (in thousands):


	June 30, 2021			December 31, 2020			Change

Accounts receivable	$	55,012		$	40,999		$	14,013
Short-term deferred revenue and customer prepayments		(3,916	)		(7,309	)		3,393
Long-term deferred revenue		(573	)		(733	)		160
Deferred expenses		980			1,650			(670	)
Sales allowances		(1,919	)		(597	)		(1,322	)

The increase in accounts receivable was primarily due to an increase in net revenues of approximately $15,381,000 in

May-June

2021 compared to November-December 2020. The decrease in short-term deferred revenue and customer prepayments was primarily due to the recognition of the associated revenue in the second quarter of 2021, as noted below. The increase in sales allowances was primarily due to the increase in the net revenues for the six months ended June 30, 2021.

Deferred expenses are included in Other current assets in the accompanying Condensed Consolidated Balance Sheets.

The Company records deferred revenue, which represents a contract liability, when cash payments are received or due in advance of performance under a contract with a customer. The Company recognized revenue of approximately $2,410,000 and $3,081,000 for the three and six months ended June 30, 2021, respectively, and $1,700,000 and $1,736,000 for the three and six months ended June 30, 2020, respectively, that was included in deferred revenue at the beginning of each respective period.