Financial Instruments and Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2016

Fair Value Disclosures [Abstract]

Schedule of Financial Instruments Measured at Fair Value on a Recurring Basis

The financial instruments measured at fair value on a recurring basis at September 30, 2016 were as follows:

	Level 1		Level 2		Level 3		Total Fair Value
Cash equivalents:
Money market funds	$	9,795	$	—	$	—	$	9,795
Commercial paper	139,463		—		—		139,463
Debt securities:
U.S. Treasury securities	99,734		—		—		99,734
Corporate debt securities	62,606		51,084		—		113,690
Preferred stock	19,185		4,047		—		23,232
Restricted investments:
Money market fund	5,640		—		—		5,640
	$	336,423	$	55,131	$	—	$	391,554

The financial instruments measured at fair value on a recurring basis at December 31, 2015 were as follows:

	Level 1		Level 2		Level 3		Total Fair Value
Cash equivalents:
Money market funds	$	18,233	$	—	$	—	$	18,233
Commercial paper	174,973		—		—		174,973
Debt securities:
U.S. Treasury securities	184,740		—		—		184,740
Corporate debt securities	—		6,292		—		6,292
Preferred stock	—		208		—		208
Restricted investments:
Guaranteed income fund	—		7,072		—		7,072
	$	377,946	$	13,572	$	—	$	391,518

Carrying Amount and Fair Value of Financial Instruments

The carrying amount and fair value of the Company’s financial instruments were as follows:

	September 30, 2016					December 31, 2015
	Carrying  value		Fair value		Level	Carrying  value		Fair value		Level
Assets
Retained interest investments	$	10,494	$	13,386	3	$	10,246	$	13,333	3
Investments held by special purpose entities:
Time deposit	$	200,000	$	200,000	3	$	200,000	$	200,000	3
U.S. Treasury securities and cash equivalents	$	8,543	$	8,759	1	$	8,785	$	9,033	1
Liabilities
Senior Notes held by special purpose entity	$	176,255	$	215,725	3	$	176,094	$	178,035	3