Derivative Instruments and Hedging Activities - Narrative (Details) $ in Thousands	12 Months Ended
	May 31, 2026 USD ($) counterparty	May 31, 2025 USD ($) agreement counterparty	May 31, 2024 USD ($) agreement
Derivative [Line Items]
Treasury rate lock, number of agreements | agreement		5	2
Derivative assets, notional amount	$ 5,550,124	$ 5,694,835
Number of counterparties subject to ratings trigger and early termination provision | counterparty	1
Treasury lock | Cash flow hedging
Derivative [Line Items]
Derivative assets, notional amount		700,000	$ 300,000
AOCI, cash flow hedge, cumulative gain (loss), after tax		1,000	1,000
Treasury lock | Derivatives
Derivative [Line Items]
Derivative assets, notional amount	$ 0	0
Reclassification of gain from AOCI to earnings			$ 8,000
Interest rate swap subject to rating trigger and early termination provision
Derivative [Line Items]
Derivative, notional amount	552,000
Unrealized gain position	39,000
Interest rate swap rating trigger
Derivative [Line Items]
Derivative, notional amount	4,692,652
Derivative, net liability position	1,000
Interest rate swaps
Derivative [Line Items]
Derivative assets, notional amount	5,550,124	5,694,835
Derivative, notional amount	$ 6,565,533	$ 7,252,235
Number of active derivative counterparties | counterparty	12	12
Number of active derivative counterparties	$ 523,544	$ 506,049
Interest rate swaps | Derivatives | Derivative Counterparty Concentration Risk
Derivative [Line Items]
Concentration risk, percentage	25.00%	25.00%