Investment Securities (Narrative) (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($) security	Dec. 31, 2019 USD ($)
Debt Securities, Available-for-sale [Line Items]
Number of held-to-maturity securities	1
Debt Securities, Available-for-sale, Restricted \| $	$ 4,800,000	$ 2,400,000
Number of securities in unrealized loss positions (in Securities)	224
Number of securities which impairment considered insignificant (in Securities)	64
Available-for-sale securities, gross unrealized loss, considered insignificant \| $	$ 398
Interest Receivable \| $	$ 108,000	83,000
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)	28
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)	7
Percentage of weighted average collateral loss	4.00%
Percentage of weighted average credit support	17.00%
Debt Instrument, Credit Rating	88.00%
Percentage of securities not rated	12.00%
Private label commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	70
Percentage of weighted average collateral loss	13.00%
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%
Single family rental real estate-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	10
Percentage of weighted average collateral loss	13.00%
Percentage of weighted average credit support	49.00%
Debt Instrument, Credit Rating	87.00%
Percentage of securities rated AA	13.00%
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss positions (in Securities)	26
Collateralized Debt Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Percentage of weighted average collateral loss	21.00%
Percentage of weighted average credit support	41.00%
Debt Instrument, Credit Rating	84.00%
Percentage of securities rated AA	13.00%
Percentage of securities rated A	3.00%
Non-mortgage asset-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	25.00%
Debt Instrument, Credit Rating	50.00%
Percentage of securities rated AA	50.00%
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 \| $	$ 23,000	$ 28,000

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 not rated

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Percentage of securities rated AA

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Percentage of weighted average collateral loss

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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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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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