Fair Value Measurements - Level 3 Significant Unobservable Inputs (Detail) $ in Millions	Dec. 31, 2020 USD ($) year month	Dec. 31, 2019 USD ($) month
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative liability | $	$ 2,065.7	$ 1,694.6
Swap | Fair Value, Measurements, Recurring | LEVEL 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative liability | $	$ 35.3	$ 33.4
Conversion Rate | Swap | Fair Value, Measurements, Recurring | LEVEL 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative liability, measurement input	1.62	1.62
Visa Class A Appreciation | Swap | Fair Value, Measurements, Recurring | LEVEL 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative liability, measurement input	0.0873	0.0854
Expected Duration | Swap | Fair Value, Measurements, Recurring | LEVEL 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative liability, measurement input | month	20	22
Expected Duration | Swap | Fair Value, Measurements, Recurring | LEVEL 3 | Lower Limit
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative liability, measurement input	12	12
Expected Duration | Swap | Fair Value, Measurements, Recurring | LEVEL 3 | Upper Limit
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative liability, measurement input | month	33	36