Revenue from Contracts with Customer (Revenue from Contracts with Customer) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Residential mortgage banking revenue, net	$ 38,438	$ 26,834
Loss on sale of investment securities, net	0	(2)
Gain on loan sales, net	1,230	1,754
Loss on junior subordinated debentures carried at fair value	0	(1,555)
BOLI income	2,070	2,069
Remaining other income	15,106	9,794
Other income	17,640	12,274
Total non-interest income	78,567	60,225
Account Service Fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	4,140	4,250
Transaction-based and overdraft service charges [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	6,256	6,359
Debit/ATM Interchange Fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	4,599	4,120
Total Service Charges on Deposits [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	14,995	14,729
Brokerage Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	4,194	4,122
Merchant Fee Income [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	841	962
Credit Card and Interchange Income [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 1,693	$ 1,518

Gain (Loss) On Changes In Fair Value Of Junior Subordinated Debentures

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Other Income, Remaining

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Earnings on or other increases in the value of the cash surrender value of bank owned life insurance policies.

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Income from mortgage banking activities (fees and commissions) and servicing real estate mortgages, credit cards, and other financial assets held by others net of any related impairment of capitalized service costs. Also includes any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans.

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No definition available.

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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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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Amount of revenue earned, classified as other, excluding interest income.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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