Marketable Securities (Tables)

3 Months Ended

Mar. 31, 2019

All marketable securities were classified as held-to-maturity as of the dates presented and the carrying amounts of held-to-maturity securities were as follows:

(in thousands)	March 31, 2019		December 31, 2018		March 31, 2018
U.S. Government and agency obligations	$	31,047	$	24,996	$	15,000
Commercial paper		—		—		24,961
Corporate bonds		5,002		5,006		—
Total short-term marketable securities		36,049		30,002		39,961
U.S. Government and agency obligations		30,000		36,098		62,287
Corporate bonds		—		—		5,018
Total long-term marketable securities		30,000		36,098		67,305
Total marketable securities	$	66,049	$	66,100	$	107,266

Scheduled maturities of held-to-maturity investments were as follows:

(in thousands)	March 31, 2019
Due within one year	$	36,049
Due in one to five years		30,000
Total	$	66,049