Derivatives and Hedging Activities (Customer Related Derivative Positions - Not Designated as Hedges) (Details) $ in Thousands	Jun. 30, 2017 USD ($) position	Dec. 31, 2016 USD ($) position
Summary of customer related derivative positions, not designated as hedging
Total	$ 75,000	$ 75,000
Fair Value	$ 578	$ 624
Not Designated as Hedging Instrument | Receive fixed, pay variable | Loan level swaps
Summary of customer related derivative positions, not designated as hedging
Number of Positions | position	235	222
Less than 1 year	$ 31,311	$ 30,245
Less than 2 years	57,570	21,708
Less than 3 years	71,039	63,771
Less than 4 years	194,784	165,783
Thereafter	560,115	567,897
Total	914,819	849,404
Fair Value	$ 12,239	$ 12,005
Not Designated as Hedging Instrument | Pay fixed, receive variable | Loan level swaps
Summary of customer related derivative positions, not designated as hedging
Number of Positions | position	220	207
Less than 1 year	$ 31,311	$ 30,245
Less than 2 years	57,570	21,708
Less than 3 years	71,039	63,771
Less than 4 years	194,784	165,783
Thereafter	560,115	567,897
Total	914,819	849,404
Fair Value	$ (12,242)	$ (12,008)
Not Designated as Hedging Instrument | Buys foreign currency, sells U.S. currency | Foreign exchange contracts
Summary of customer related derivative positions, not designated as hedging
Number of Positions | position	24	33
Less than 1 year	$ 43,032	$ 45,711
Total	43,032	45,711
Fair Value	$ 1,862	$ (2,250)
Not Designated as Hedging Instrument | Buys U.S. currency, sells foreign currency | Foreign exchange contracts
Summary of customer related derivative positions, not designated as hedging
Number of Positions | position	24	33
Less than 1 year	$ 43,032	$ 45,711
Total	43,032	45,711
Fair Value	$ (1,845)	$ 2,277