Derivative Financial Instruments - Summary of Outstanding Foreign Exchange Derivatives Designated as Net Investment Hedges of Foreign Currency Risk (Detail) - Designated as Hedging Instrument [Member] - Net Investment Hedges [Member] € in Thousands, £ in Thousands, $ in Thousands, $ in Thousands	Jun. 30, 2020 CAD ($) DerivativeInstrument	Jun. 30, 2020 EUR (€) DerivativeInstrument	Jun. 30, 2020 GBP (£) DerivativeInstrument	Jun. 30, 2020 AUD ($) DerivativeInstrument	Dec. 31, 2019 CAD ($) DerivativeInstrument	Dec. 31, 2019 EUR (€) DerivativeInstrument	Dec. 31, 2019 GBP (£) DerivativeInstrument	Dec. 31, 2019 AUD ($) DerivativeInstrument
Buy USD / Sell EUR Forward [Member] | EUR [Member]
Derivative [Line Items]
Number of Instruments	7	7	7	7
Notional Amount | €		€ 607,690
Buy USD / Sell EUR Forward [Member] | GBP [Member]
Derivative [Line Items]
Number of Instruments					5	5	5	5
Notional Amount | €						€ 525,600
Buy USD / Sell GBP Forward [Member] | EUR [Member]
Derivative [Line Items]
Number of Instruments					4	4	4	4
Notional Amount | £							£ 527,100
Buy USD / Sell GBP Forward [Member] | GBP [Member]
Derivative [Line Items]
Number of Instruments	5	5	5	5
Notional Amount | £			£ 385,087
Buy USD / Sell AUD Forward [Member] | AUD [Member]
Derivative [Line Items]
Number of Instruments	1	1	1	1	3	3	3	3
Notional Amount | $				$ 92,800				$ 135,600
Buy USD / Sell CAD Forward [Member] | CAD [Member]
Derivative [Line Items]
Number of Instruments	2	2	2	2	1	1	1	1
Notional Amount | $	$ 24,400				$ 23,200