Fair Value Measurement (Tables)

6 Months Ended

Jun. 30, 2019

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

The following tables summarize significant assets and liabilities measured at fair value in the condensed consolidated balance sheets on a recurring basis for each of the fair value levels (in thousands):

	Fair Value Measurement at Reporting Date Using
June 30, 2019	Level 1		Level 2		Level 3		Total
Cash equivalents
Money market funds	$	17,790	$	—	$	—	$	17,790
Other noncurrent assets
Restricted cash		5,825		—		—		5,825
Total assets	$	23,615	$	—	$	—	$	23,615
Other current liabilities
Interest rate cash flow hedge	$	—	$	4,985	$	—	$	4,985
Total liabilities	$	—	$	4,985	$	—	$	4,985
December 31, 2018
Cash equivalents
Money market funds	$	84,613	$	—	$	—	$	84,613
Other noncurrent assets
Restricted cash		5,825		—		—		5,825
Total assets	$	90,438	$	—	$	—	$	90,438
Other current liabilities
Interest rate cash flow hedge	$	—	$	1,098	$	—	$	1,098
Total liabilities	$	—	$	1,098	$	—	$	1,098
June 30, 2018
Cash equivalents
Money market funds	$	56,534	$	—	$	—	$	56,534
Other current assets
Interest rate cash flow hedge		—		473		—		473
Other noncurrent assets
Restricted cash		5,746		—		—		5,746
Total assets	$	62,280	$	473	$	—	$	62,753

Schedule of Carrying and Fair Value Amounts

The carrying values and estimated fair values of our financial instruments that are not required to be recorded at fair value in the condensed consolidated balance sheets were as follows:

		June 30, 2019				December 31, 2018				June 30, 2018
(in thousands)	Fair Value Hierarchy	Carrying Value		Fair Value		Carrying Value		Fair Value		Carrying Value		Fair Value
Assets:
Held-to-maturity marketable    securities	Level 1	$	61,037	$	60,887	$	66,100	$	65,290	$	81,205	$	80,006
Liabilities (including current maturities):
2019 Notes1	Level 3	$	40,000	$	40,571	$	40,000	$	40,484	$	80,000	$	81,307
Credit Agreement - term    loan1	Level 3		142,500		143,109		146,250		147,141		150,000		150,608
Credit Agreement -    revolving credit facility1	Level 3		220,000		220,597		197,000		197,889		99,000		99,267
Convertible notes	Level 1		—		—		—		—		160,765		186,410

¹See Note 14 for definitions of, and more information about, the 2019 Notes and Credit Agreement.