Fair Value of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2018

Fair Value Disclosures [Abstract]

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

Our assets and liabilities that were measured at fair value on a recurring basis were as follows (in thousands):

	March 31, 2018								December 31, 2017
	Fair Value		Level I		Level II		Level III		Fair Value		Level I		Level II		Level III
Money market    funds	$	931,548	$	931,548	$	—	$	—	$	2,163,459	$	2,163,459	$	—	$	—
Interest rate swaps,    net		10,488		—		10,488		—		59		—		59		—
Total	$	942,036	$	931,548	$	10,488	$	—	$	2,163,518	$	2,163,459	$	59	$	—

Schedule of Interest Rate Swaps Outstanding

Our interest rate swaps outstanding were as follows as of March 31, 2018 (in thousands):

	Aggregate Notional Amount		Gross Asset at Fair Value		Gross Liability at Fair Value		Gross Gains		Gross Losses
Interest rate swaps	$	479,247	$	11,181	$	693	$	9,663	$	35

Our interest rate swaps outstanding were as follows as of December 31, 2017 (in thousands):

	Aggregate Notional Amount		Gross Asset at Fair Value		Gross Liability at Fair Value		Gross Gains		Gross Losses
Interest rate swaps	$	496,544	$	5,304	$	5,245	$	7,192	$	13,082

Schedule of Estimated Fair Values and Carrying Values

The following table presents the estimated fair values and the carrying values (in thousands):

	March 31, 2018				December 31, 2017
	CarryingValue		Fair Value		CarryingValue		Fair Value
Convertible senior notes	$	3,763,803	$	4,106,733	$	3,722,673	$	4,488,651
Senior notes	$	1,776,340	$	1,570,500	$	1,775,550	$	1,732,500
Participation interest	$	17,937	$	17,407	$	17,545	$	17,042
Solar asset-backed notes	$	869,780	$	888,365	$	880,415	$	898,145
Solar loan-backed notes	$	220,593	$	228,970	$	236,844	$	248,149
Automotive asset-backed notes	$	511,587	$	512,256	$	—	$	—