At March 31, 2019 and December 31, 2018, cash and cash equivalents included bank balances and investments with original maturities less than 90 days. At March 31, 2019 and December 31, 2018, the Company’s cash equivalents were invested in highly liquid AAA rated money market funds that are required to comply with Rule 2a-7 of the Investment Company Act of 1940. Such funds utilize the amortized cost method of accounting, seek to maintain a constant $1.00 per share price, and are redeemable upon demand. The Company restricts its investments in AAA money market funds to those invested 100% in either short-term U.S. government agency securities or bank repurchase agreements collateralized by these same securities. The fair values of these money market funds are established through quoted prices in active markets for identical assets (Level 1 inputs). The Company’s cash in U.S. banks is insured by the Federal Deposit Insurance Corporation up to the insurable limit of $250.

The Company had $1.1 million and $0.8 million of cash and cash equivalents in foreign bank accounts at March 31, 2019 and December 31, 2018, respectively. The Company’s cash in its foreign bank accounts is not insured. Within the cash in foreign bank accounts, the Company had cash of $0.9 million and $0.6 million in China bank accounts at March 31, 2019 and December 31, 2018, respectively. As of March 31, 2019, the Company has no intentions of repatriating the cash in its foreign bank accounts in China. If the Company decides to repatriate the cash in the foreign bank accounts, it may have trouble in doing so in a timely manner. The Company may also be exposed to foreign currency fluctuations and taxes if it repatriates these funds. The Company completed the closure of its Israeli subsidiary during the fourth quarter of 2018. The Company expects to repatriate the subsidiary’s remaining cash of $0.2 million in 2019. The Company does not expect the foreign currency exchange rate related to the repatriation of these funds to have a material impact on the financial statements.

At March 31, 2019 and December 31, 2018, the Company’s short-term investments consisted of U.S. government agency bonds, A or higher rated corporate bonds, and certificates of deposit. All the investments at March 31, 2019 and December 31, 2018 were classified as held-to-maturity. The bonds have original maturities greater than 90 days and mature in less than one year. The Company’s bond investments are recorded at the purchase price and carried at amortized cost.

Cash equivalents and investments were as follows at March 31, 2019 and December 31, 2018:

	March 31, 2019								December 31, 2018
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Cash equivalents:
Corporate bonds	$	0	$	999	$	0	$	999	$	0	$	1,156	$	0	$	1,156
Certificates of deposit		1,312		0		0		1,312		0		0		0		0
Money market funds		49		0		0		49		1,688		0		0		1,688
Total Cash Equivalents	$	1,361	$	999	$	0	$	2,360	$	1,688	$	1,156	$	0	$	2,844
Investments:
Corporate bonds	$	0	$	24,311	$	0	$	24,311	$	0	$	21,583	$	0	$	21,583
US government agency bonds		0		4,032		0		4,032		0		5,671		0		5,671
Certificates of deposit		2,243		0		0		2,243		3,616		0		0		3,616
Total Investments	$	2,243	$	28,343	$	0	$	30,586	$	3,616	$	27,254	$	0	$	30,870
Cash equivalents and Investments - book value	$	3,604	$	29,342	$	0	$	32,946	$	5,304	$	28,410	$	0	$	33,714

Cash equivalents and Investments - fair value	$	3,604	$	29,293	$	0	$	32,897	$	5,304	$	28,389	$	0	$	33,693

The Company categorizes its financial instruments within a fair value hierarchy according to accounting guidance for fair value. The fair value hierarchy is described under the Fair Value of Financial Instruments in Note 2. For the Level 2 investments, the Company uses quoted prices of similar assets in active markets. The fair values in the table above reflect net unrealized losses of $49 and $21 at March 31, 2019 and December 31, 2018, respectively.