Available-for-sale securities, Gross Unrealized Loss, Considered Insignificant for OTTI Analysis

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Number Of Held-To-Maturity Securities

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Number of securities which impairment was considered insignificant.

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Percentage of securities rated AA

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Percentage of securities rated AAA

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- Definition

Percentage of weighted average collateral loss

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Percentage of weighted average credit support

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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Amount of restricted 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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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Investment Securities (Narrative) (Details) $ in Thousands	9 Months Ended
Investment Securities (Narrative) (Details) $ in Thousands	Sep. 30, 2020 USD ($) security	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	180
Number of held-to-maturity securities	1
Debt Securities, Available-for-sale, Restricted \| $	$ 4,400,000		$ 2,400,000
Number of securities which impairment considered insignificant (in Securities)	37
Available-for-sale securities, gross unrealized loss, considered insignificant \| $	$ 300
Interest Receivable \| $	105,000		83,000
Financing Receivable, Allowance for Credit Loss \| $	$ 274,128	$ 266,123	108,671	$ 108,462	$ 112,141	$ 109,931
U.S. Government agency and sponsored enterprise residential MBS
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	29
U.S. Government agency and sponsored enterprise commercial MBS
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	5
Private label residential mortgage-backed securities and CMOs
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	5
Percentage of weighted average collateral loss	4.00%
Percentage of weighted average credit support	19.00%
Debt Instrument, Credit Rating	100.00%
Private label commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	65
Percentage of weighted average collateral loss	12.00%
Percentage of weighted average credit support	42.00%
Debt Instrument, Credit Rating	83.00%
Percentage of securities rated AA	12.00%
Percentage of securities rated A	5.00%
Financing Receivable, Allowance for Credit Loss \| $	$ 600
Single family rental real estate-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	3
Percentage of weighted average collateral loss	14.00%
Percentage of weighted average credit support	44.00%
Debt Instrument, Credit Rating	88.00%
Percentage of securities rated AA	12.00%
Collateralized Debt Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	23
Percentage of weighted average collateral loss	22.00%
Percentage of weighted average credit support	42.00%
Debt Instrument, Credit Rating	80.00%
Percentage of securities rated AA	16.00%
Percentage of securities rated A	4.00%
Non-mortgage asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	2
Percentage of weighted average collateral loss	10.00%
Percentage of weighted average credit support	22.00%
Percentage of securities rated AA	100.00%
SBA securities
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	11
Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Interest Receivable \| $	$ 18,000		$ 28,000