Derivative Instruments and Hedging Activities - Consolidated Statements of Financial Condition Related to Fair Value of Derivative Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Derivatives Designated as Hedging Instruments [Member]
Derivative [Line Items]
Notional Amount, Fair Value	$ 1,140,546	$ 1,191,591
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedge Interest Rate Caps and Swaps [Member]
Derivative [Line Items]
Notional Amount, Fair Value	1,007,000	1,007,000
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedge Interest Rate Swaps [Member]
Derivative [Line Items]
Notional Amount, Fair Value	133,546	184,591
Derivatives Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Notional Amount, Fair Value	299,865	306,616
Derivatives Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Notional Amount, Fair Value	270,591	259,832
Derivatives Not Designated as Hedging Instrument [Member] | Mortgage Banking Derivatives [Member]
Derivative [Line Items]
Notional Amount, Fair Value	29,274	46,784
Other Assets [Member] | Derivatives Designated as Hedging Instruments [Member]
Derivative [Line Items]
Asset Derivatives, Fair Value	5,242	9,982
Other Assets [Member] | Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedge Interest Rate Caps and Swaps [Member]
Derivative [Line Items]
Asset Derivatives, Fair Value	5,242	9,883
Other Assets [Member] | Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedge Interest Rate Swaps [Member]
Derivative [Line Items]
Asset Derivatives, Fair Value	0	99
Other Assets [Member] | Derivatives Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Asset Derivatives, Fair Value	5,489	5,140
Other Assets [Member] | Derivatives Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Asset Derivatives, Fair Value	5,449	4,823
Other Assets [Member] | Derivatives Not Designated as Hedging Instrument [Member] | Mortgage Banking Derivatives [Member]
Derivative [Line Items]
Asset Derivatives, Fair Value	40	317
Other Liabilities [Member] | Derivatives Designated as Hedging Instruments [Member]
Derivative [Line Items]
Liability Derivatives, Fair Value	13,018	15,616
Other Liabilities [Member] | Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedge Interest Rate Caps and Swaps [Member]
Derivative [Line Items]
Liability Derivatives, Fair Value	11,379	10,925
Other Liabilities [Member] | Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedge Interest Rate Swaps [Member]
Derivative [Line Items]
Liability Derivatives, Fair Value	1,639	4,691
Other Liabilities [Member] | Derivatives Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Liability Derivatives, Fair Value	5,492	4,970
Other Liabilities [Member] | Derivatives Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Liability Derivatives, Fair Value	5,449	4,823
Other Liabilities [Member] | Derivatives Not Designated as Hedging Instrument [Member] | Mortgage Banking Derivatives [Member]
Derivative [Line Items]
Liability Derivatives, Fair Value	$ 43	$ 147