Derivatives and Hedging Activities Derivatives Fair Value and Balance Sheet Classification (Details) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	$ 16,667	$ 17,047
Other Assets [Member] | Designated as Hedging Instrument [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	0	0
Other Assets [Member] | Not Designated as Hedging Instrument [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	16,654	17,032
Other Assets [Member] | Not Designated as Hedging Instrument [Member] | Loan Participations and Assignments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	13	15
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	[1]	(17,175)	(17,606)
Other Liabilities [Member] | Designated as Hedging Instrument [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	[1]	(666)	(1,040)
Other Liabilities [Member] | Not Designated as Hedging Instrument [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	[1]	(16,504)	(16,560)
Other Liabilities [Member] | Not Designated as Hedging Instrument [Member] | Loan Participations and Assignments [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	[1]	$ (5)	$ (6)

[1] For additional details, see Part I. Item 1. “Notes to Unaudited Consolidated Financial Statements-Note 5: Fair Value Measurements.”