Investment Securities Gross Unrealized Losses - AFS (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized loss position, less than twelve months, fair value	$ 36,174	$ 198,488
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(217)	(10,320)
Continuous unrealized loss position, 12 months or longer, fair value	115,284	4,692
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(5,280)	(3,356)
Total, continuous unrealized loss position, fair value	151,458	203,180
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(5,497)	(13,676)
U.S. government agencies and corporations [Member]
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized loss position, less than twelve months, fair value	5,058
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(1)
Continuous unrealized loss position, 12 months or longer, fair value	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Total, continuous unrealized loss position, fair value	5,058
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(1)
State and political subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sales securities in unrealized loss positions, qualitative disclosure, number of positions, greater than or equal to one year	19
Continuous unrealized loss position, less than twelve months, fair value	10,068	49,324
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(101)	(4,342)
Continuous unrealized loss position, 12 months or longer, fair value	11,452	1,439
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(242)	(169)
Total, continuous unrealized loss position, fair value	21,520	50,763
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(343)	(4,511)
Collateralized mortgage obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sales securities in unrealized loss positions, qualitative disclosure, number of positions, greater than or equal to one year	16
Continuous unrealized loss position, less than twelve months, fair value	16,041	96,744
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(95)	(3,911)
Continuous unrealized loss position, 12 months or longer, fair value	64,482	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,677)	0
Total, continuous unrealized loss position, fair value	80,523	96,744
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(1,772)	(3,911)
Mortgage-backed securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sales securities in unrealized loss positions, qualitative disclosure, number of positions, greater than or equal to one year	8
Continuous unrealized loss position, less than twelve months, fair value	0	44,224
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(1,677)
Continuous unrealized loss position, 12 months or longer, fair value	33,174	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(623)	0
Total, continuous unrealized loss position, fair value	33,174	44,224
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(623)	(1,677)
Trust preferred securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sales securities in unrealized loss positions, qualitative disclosure, number of positions, greater than or equal to one year	2
Continuous unrealized loss position, less than twelve months, fair value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Continuous unrealized loss position, 12 months or longer, fair value	3,343	2,745
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(2,588)	(3,178)
Total, continuous unrealized loss position, fair value	3,343	2,745
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(2,588)	(3,178)
Corporate notes and equity securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized loss position, less than twelve months, fair value	5,007	8,196
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(20)	(390)
Continuous unrealized loss position, 12 months or longer, fair value	2,833	508
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(150)	(9)
Total, continuous unrealized loss position, fair value	7,840	8,704
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ (170)	$ (399)
Corporate note securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sales securities in unrealized loss positions, qualitative disclosure, number of positions, greater than or equal to one year	3
Equity securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sales securities in unrealized loss positions, qualitative disclosure, number of positions, greater than or equal to one year	3