Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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Investment Securities Investment Securities (Narrative) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Proceeds from Sale of Available-for-sale Securities	$ 8,963	$ 0
Available-for-sale Securities, Gross Realized Gains	8	$ 0
Debt Securities, Available-for-sale	3,016,631		$ 2,925,833
Pledged Financial Instruments, Not Separately Reported, Securities	4,000,000		2,700,000
Agency CMO [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt Securities, Available-for-sale	204,830		185,801
Agency MBS [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt Securities, Available-for-sale	1,612,818		1,612,164
Agency CMBS [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt Securities, Available-for-sale	697,682		581,552
Non-agency CMBS [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt Securities, Available-for-sale	409,023		431,871
CLO [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt Securities, Available-for-sale	81,398		92,205
Corporate Debt Securities [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Proceeds from Sale of Available-for-sale Securities	9,000
Debt Securities, Available-for-sale	10,880		$ 22,240
Callable at the option of the counterparty [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt Securities, Available-for-sale	$ 1,200,000