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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- Definition

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	12 Months Ended
Investment Securities (Narrative) (Details) $ in Thousands	Dec. 31, 2020 USD ($) security	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Securities, Available-for-sale [Line Items]
Number of held-to-maturity securities	1
Interest Receivable \| $	$ 99,000	$ 83,000
Debt Securities, Available-for-sale, Restricted \| $	$ 4,100,000	2,400,000
Number of securities in unrealized loss positions (in Securities)	148
Number of securities which impairment considered insignificant (in Securities)	24
Available-for-sale securities, gross unrealized loss, considered insignificant \| $	$ 300
Financing Receivable, Allowance for Credit Loss \| $	$ 257,323	108,671	$ 109,931	$ 144,795
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	1
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)	20
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)	7
Private label residential mortgage-backed securities and CMOs
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	3
Percentage of weighted average collateral loss	4.00%
Percentage of weighted average credit support	18.00%
Private label commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	59
Percentage of weighted average collateral loss	12.00%
Percentage of weighted average credit support	42.00%
Financing Receivable, Allowance for Credit Loss \| $	$ 400
Debt Instrument, Credit Rating	85.00%
Percentage of securities rated AA	9.00%
Percentage of securities rated A	6.00%
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	21
Collateralized Debt Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Percentage of weighted average collateral loss	23.00%
Percentage of weighted average credit support	42.00%
Debt Instrument, Credit Rating	81.00%
Percentage of securities rated AA	15.00%
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	9.00%
Percentage of weighted average credit support	22.00%
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 \| $	$ 17,000	$ 28,000