Business Segment Information (Amounts Of Consolidated Revenue, Expense, Tax And Assets) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($) segment	Mar. 31, 2017 USD ($)
Segment Reporting, Measurement Disclosures [Abstract]
Number of Operating Segments \| segment	4
Segment Reporting Information [Line Items]
Net interest income	$ 301,173	$ 189,708
Provision/(provision credit) for loan losses	(1,000)	(1,000)
Noninterest income	136,017	116,939
Noninterest expense	313,265	222,205
Income/(loss) before income taxes	124,925	85,442
Provision/(benefit) for income taxes	29,931	27,054
Net income/(loss)	94,994	58,388
Average assets	40,350,514	28,806,106
Regional Banking
Segment Reporting Information [Line Items]
Net interest income	298,699	193,082
Provision/(provision credit) for loan losses	5,312	3,098
Noninterest income	78,853	58,978
Noninterest expense	205,201	148,050
Income/(loss) before income taxes	167,039	100,912
Provision/(benefit) for income taxes	39,362	36,476
Net income/(loss)	127,677	64,436
Average assets	28,474,692	17,955,627
Fixed Income
Segment Reporting Information [Line Items]
Net interest income	8,463	1,156
Noninterest income	45,605	50,823
Noninterest expense	50,544	48,707
Income/(loss) before income taxes	3,524	3,272
Provision/(benefit) for income taxes	742	1,018
Net income/(loss)	2,782	2,254
Average assets	3,481,214	1,875,488
Corporate Segment
Segment Reporting Information [Line Items]
Net interest income	(13,190)	(13,771)
Noninterest income	9,479
Noninterest expense	51,116	16,874
Income/(loss) before income taxes	(54,827)	(25,169)
Provision/(benefit) for income taxes	(12,444)	(12,929)
Net income/(loss)	(42,383)	(12,240)
Average assets	7,110,129	7,358,788
Non-Strategic
Segment Reporting Information [Line Items]
Net interest income	7,201	9,241
Provision/(provision credit) for loan losses	(6,312)	(4,098)
Noninterest income	2,080	1,662
Noninterest expense	6,404	8,574
Income/(loss) before income taxes	9,189	6,427
Provision/(benefit) for income taxes	2,271	2,489
Net income/(loss)	6,918	3,938
Average assets	$ 1,284,479	$ 1,616,203

Amount of average assets attributed to the reportable segment.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.4-08.(h)(1)(i))
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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The net amount of operating interest income (expense).

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Total aggregate amount of all noninterest expense.

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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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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