Securities (Available for Sale Securities Losses) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	$ 356,862	$ 151,824
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(9,314)	(2,321)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	24,489	90,587
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	(914)	(4,709)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	381,351	242,411
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses	(10,228)	(7,030)
U.S. Government Corporations and Agencies
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	1,517	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(1)	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	1,517	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses	(1)	0
Mortgage-Backed Securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	332,842	133,538
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(9,121)	(1,794)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	24,489	71,231
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	(914)	(3,203)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	357,331	204,769
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses	(10,035)	(4,997)
Obligations of States and Political Subdivisions
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	22,503	13,139
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(192)	(284)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0	4,010
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	0	(689)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	22,503	17,149
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses	(192)	(973)
Corporate Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	0	5,147
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	0	(243)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0	15,346
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	0	(817)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	0	20,493
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses	0	(1,060)
Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	356,862	151,824
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(9,314)	(2,321)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	24,489	90,587
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	(914)	(4,709)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	381,351	242,411
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses	(10,228)	(7,030)
Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Unrealized Losses	$ 0	$ 0