Derivative Financial Instruments (Net gains or losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Derivative Instruments, Gain (Loss)
Net gains (losses) recognized in income	$ 1,258	$ 1,550
Interest Rate Lock Commitments | Mortgage Banking Income
Derivative Instruments, Gain (Loss)
Net gains (losses) recognized in income	587	1,101
Forward Commitments | Mortgage Banking Income
Derivative Instruments, Gain (Loss)
Net gains (losses) recognized in income	22	(354)
Interest Rate Swap Agreements | Other Noninterest Income
Derivative Instruments, Gain (Loss)
Net gains (losses) recognized in income	0	4
Foreign Exchange Contracts | Other Noninterest Income
Derivative Instruments, Gain (Loss)
Net gains (losses) recognized in income	$ 649	$ 799