In connection with certain sales in Asia, the Company accepts a bank promissory note as customer payment. The notes may be presented for payment at maturity, which is less than one year.

The Company also maintains allowances for doubtful accounts for estimated losses resulting from the inability of its customers to make required payments. The Company determines the allowance based on historical write-off experience, customer-specific facts and economic conditions. If the financial condition of the Company’s customers were to deteriorate, resulting in an impairment of their ability to make payments, additional allowances may be required.

As of June 30, 2019 and December 31, 2018, Accounts receivable consisted of the following:

(in thousands)	June 30, 2019	December 31, 2018
Trade and other accounts receivable	$214,045	$211,244
Bank promissory notes	14,680	19,269
Allowance for doubtful accounts	(8,141)	(7,337)
Accounts receivable, net	$220,584	$223,176

The Company has Noncurrent receivables in the AEC segment that represent revenue earned which has extended payment terms. The Noncurrent receivables will be invoiced to the customer, with 2% interest, over a 10-year period starting in 2020.

As of June 30, 2019 and December 31, 2018, Noncurrent receivables consisted of the following:

Index

(in thousands)

June 30, 2019

December 31, 2018

Noncurrent receivables

$45,651

$45,061