Debt Facilities - Convertible Debt (Detail) - USD ($)		3 Months Ended
	Jun. 15, 2016	Jun. 30, 2016	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015
Debt Instrument [Line Items]
Long-term debt, gross			$ 1,589,414,000	$ 1,243,699,000
Less amount representing debt discount and debt issuance cost			(14,015,000)	(2,681,000)
Long-term debt, net			5,441,418,000
Convertible debt			0	146,121,000
Additional paid-in capital			$ 7,371,024,000	4,838,444,000
4.75% convertible subordinated notes
Debt Instrument [Line Items]
Convertible debt interest rate	4.75%		4.75%		4.75%
Convertible debt		$ 150,082,000
Debt conversion, converted instrument, shares issued		1,981,662
Cash		$ 3,619,000
Capped call premium		$ 49,664,000
Additional paid-in capital	$ 141,688,000
Conversion price per share (in dollars per share)	$ 372.10
Convertible subordinated debt | 4.75% convertible subordinated notes
Debt Instrument [Line Items]
Long-term debt, gross			$ 0	150,082,000
Less amount representing debt discount and debt issuance cost			0	(3,961,000)
Long-term debt, net			$ 0	$ 146,121,000
Convertible debt interest rate			4.75%	4.75%
Common stock | 4.75% convertible subordinated notes
Debt Instrument [Line Items]
Debt conversion, converted instrument, shares issued	380,779