v3.21.2

Interest Rate Swaps - Summary of Interest-rate Swap Agreements (Parenthetical) (Detail) - Interest Rate Swap	9 Months Ended
	Sep. 30, 2021
Derivative [Line Items]
Interest rate swap terminated month and year	2021-09
M&T Bank | Umbrella Partnership Real Estate Investment Trust Transaction
Derivative [Line Items]
Interest rate swap assumed month and year	2017-10

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- Definition

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- Definition

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- Definition

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+ References

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