Derivatives (Fair Values of Derivative Financial Instruments) (Details) - USD ($) $ in Thousands		Jun. 30, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Fair Values, Assets	[1]	$ 43,903	$ 23,251
Fair Values, Liabilities	[1]	43,184	23,968
Derivatives Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Notional Amounts		800,000	500,000
Fair Values, Assets	[2]	3,330
Fair Values, Liabilities	[2]		281
Derivatives Not Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Notional Amounts		1,148,279	1,002,350
Fair Values, Assets	[2]	40,573	23,251
Fair Values, Liabilities	[2]	43,184	23,687
Derivatives Not Designated as Hedging Instruments [Member] | Interest Rate Swaps [Member]
Derivatives, Fair Value [Line Items]
Notional Amounts	[3]	856,332	780,871
Fair Values, Assets	[2],[3]	38,389	20,622
Fair Values, Liabilities	[2],[3]	40,202	21,007
Derivatives Not Designated as Hedging Instruments [Member] | Risk Participation Agreements [Member]
Derivatives, Fair Value [Line Items]
Notional Amounts		88,946	83,430
Fair Values, Assets	[2]	114	83
Fair Values, Liabilities	[2]	243	162
Derivatives Not Designated as Hedging Instruments [Member] | Forward Commitments to Sell Residential Mortgage Loans [Member]
Derivatives, Fair Value [Line Items]
Notional Amounts		105,357	55,128
Fair Values, Assets	[2]	23	263
Fair Values, Liabilities	[2]	1,404	336
Derivatives Not Designated as Hedging Instruments [Member] | Interest Rate-Lock Commitments on Residential Mortgage Loans [Member]
Derivatives, Fair Value [Line Items]
Notional Amounts		62,622	38,853
Fair Values, Assets	[2]	703	243
Fair Values, Liabilities	[2]	12	167
Derivatives Not Designated as Hedging Instruments [Member] | Foreign Exchange Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Notional Amounts		35,022	44,068
Fair Values, Assets	[2]	1,344	2,040
Fair Values, Liabilities	[2]	1,323	2,015
Cash Flow Hedge [Member] | Derivatives Designated as Hedging Instruments [Member] | Interest Rate Swaps [Member]
Derivatives, Fair Value [Line Items]
Notional Amounts		800,000	500,000
Fair Values, Assets	[2]	$ 3,330
Fair Values, Liabilities	[2]		$ 281

[1] For further disaggregation of derivative assets and liabilities, see Note 6 - Derivatives.

[2] Derivative assets and liabilities are reported with other assets or other liabilities, respectively, in the consolidated balance sheets.

[3] The notional amount represents both the customer accommodation agreements and offsetting agreements with unrelated financial institutions.