Financial Instruments and Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2017

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 June 30, 2017 were as follows:

	Level 1		Level 2		Level 3		Total Fair Value
Cash equivalents:
Money market funds	$	14,447	$	—	$	—	$	14,447
Commercial paper	207,202		—		—		207,202
	221,649		—		—		221,649
Investments:
U.S. Treasury securities	24,923		—		—		24,923
Corporate debt securities	—		96,019		—		96,019
Preferred stock	11,345		28,932		—		40,277
Common stock	6,523		—		—		6,523
	42,791		124,951		—		167,742
Restricted investments:
Short-term bond	4,250		—		—		4,250
Money market fund	219		—		—		219
	4,469		—		—		4,469
	$	268,909	$	124,951	$	—	$	393,860

The financial instruments measured at fair value on a recurring basis at December 31, 2016 were as follows:

	Level 1		Level 2		Level 3		Total Fair Value
Cash equivalents:
Money market funds	$	86,236	$	—	$	—	$	86,236
Commercial paper	129,671		—		—		129,671
	215,907		—		—		215,907
Investments:
Corporate debt securities	57,788		81,344		—		139,132
Preferred stock	19,177		17,416		—		36,593
	76,965		98,760		—		175,725
Restricted investments:
Short-term bond	4,226		—		—		4,226
Money market fund	1,410		—		—		1,410
	5,636		—		—		5,636
	$	298,508	$	98,760	$	—	$	397,268

Carrying Amount and Fair Value of Financial Instruments

The carrying amount and fair value, measured on a nonrecurring basis, of the Company’s financial instruments were as follows:

	June 30, 2017					December 31, 2016
	Carrying  value		Fair value		Level	Carrying  value		Fair value		Level
Assets
Retained interest investments	$	10,909	$	13,868	3	$	10,635	$	13,669	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	$	8,267	$	8,155	1	$	8,590	$	8,398	1
Liabilities
Senior notes held by special purpose entity	$	176,422	$	200,481	3	$	176,310	$	199,691	3