Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2017

Marketable Securities [Abstract]

Schedule of Marketable Securities

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)	September 30, 2017		December 31, 2016		September 30, 2016
U.S. Government and agency obligations	$	12,909	$	10,002	$	14,999
Commercial paper	34,905		54,882		39,864
Total short-term marketable securities	47,814		64,884		54,863
U.S. Government and agency obligations	69,991		62,895		52,908
Total long-term marketable securities	69,991		62,895		52,908
Total marketable securities	$	117,805	$	127,779	$	107,771

Held-to-maturity Securities

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

(in thousands)	September 30, 2017
Due within one year	$	47,814
Due in one to five years	69,991
Total	$	117,805