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Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Mar. 31, 2018	Jan. 01, 2018	Jan. 01, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Adjustment from adoption of new accounting standard		$ (5,973)			$ 269,776	$ 1,123
Assets:
Publicly traded equity securities	$ 2,779		$ 1,717
Derivative instruments	76,640		73,074
Liabilities:
Derivative instruments	45,832		9,740
Fair value, measurements, recurring
Assets:
Publicly traded equity securities	2,779		1,717
Derivative instruments	57,707		73,074
Assets	954,616		197,132
Liabilities:
Derivative instruments	35,612		9,740
Fair value, measurements, recurring \| Money market and deposit accounts
Assets:
Investments	886,547		119,518
Fair value, measurements, recurring \| Certificates of deposit
Assets:
Investments	7,583		2,823
Fair value, measurements, recurring \| Fair value, Inputs, Level 1
Assets:
Publicly traded equity securities	2,779		1,717
Derivative instruments	0		0
Assets	889,326		121,235
Liabilities:
Derivative instruments	0		0
Fair value, measurements, recurring \| Fair value, Inputs, Level 1 \| Money market and deposit accounts
Assets:
Investments	886,547		119,518
Fair value, measurements, recurring \| Fair value, Inputs, Level 1 \| Certificates of deposit
Assets:
Investments	0		0
Fair value, measurements, recurring \| Fair value, Inputs, Level 2
Assets:
Publicly traded equity securities	0		0
Derivative instruments	57,707		73,074
Assets	65,290		75,897
Liabilities:
Derivative instruments	35,612		9,740
Fair value, measurements, recurring \| Fair value, Inputs, Level 2 \| Money market and deposit accounts
Assets:
Investments	0		0
Fair value, measurements, recurring \| Fair value, Inputs, Level 2 \| Certificates of deposit
Assets:
Investments	$ 7,583		$ 2,823
Accounting Standards Update 2016-01
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Adjustment from adoption of new accounting standard				$ 2,100
Retained Earnings
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Adjustment from adoption of new accounting standard		$ (5,973)			271,900	$ 1,123
Retained Earnings \| Accounting Standards Update 2016-01
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Adjustment from adoption of new accounting standard					$ 2,100