Investment Securities (Gross Unrealized Loss Table) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013 securities	Dec. 31, 2012 securities
Securities available for sale
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 1,908,543	$ 213,685
Available-for-sale Securities, Continous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(67,758)	(1,031)
Available for Sale Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	218	41.000
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	199,691	50,056
available for sale securities, continuous unrealized loss position, 12 months or longer, aggregate loss at end of period	(22,462)	(11,891)
Available for Sale Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	46.000	11.000
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	2,108,234	263,741
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(90,220)	(12,922)
Securities held to maturity
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	2,373,148	23,956
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(118,026)	(86)
Held to Maturity Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	492	13.000
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	2,478	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss at End of Period	(183)	0
Held to Maturity Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	6.000	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	2,375,626	23,956
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(118,209)	(86)
U.S. Government agencies
Securities held to maturity
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	23,652
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(1,348)
Held to Maturity Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	1
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss at End of Period	0
Held to Maturity Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	23,652
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(1,348)
U.S. States and political subdivisions
Securities available for sale
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	38,039	14,110
Available-for-sale Securities, Continous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(1,996)	(229)
Available for Sale Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	65	24
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	14,157	0
available for sale securities, continuous unrealized loss position, 12 months or longer, aggregate loss at end of period	(1,800)	0
Available for Sale Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	25	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	52,196	14,110
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(3,796)	(229)
Securities held to maturity
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	222,154	6,543
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(10,276)	(70)
Held to Maturity Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	353	12
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	2,478	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss at End of Period	(183)	0
Held to Maturity Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	6	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	224,632	6,543
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(10,459)	(70)
Residential Mortgage Backed Securities Issued by US Government Sponsored Enterprises
Securities available for sale
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	434,761	14
Available-for-sale Securities, Continous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(13,109)	0
Available for Sale Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	35	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	14,890	13
available for sale securities, continuous unrealized loss position, 12 months or longer, aggregate loss at end of period	(1,318)	0
Available for Sale Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	2	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	449,651	27
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(14,427)	0
Securities held to maturity
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	422,192
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(11,617)
Held to Maturity Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	22
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss at End of Period	0
Held to Maturity Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	422,192
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(11,617)
Commercial Mortgage Backed Securities Issued by US Government Sponsored Enterprises
Securities available for sale
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	33,387	31,237
Available-for-sale Securities, Continous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(1,491)	(406)
Available for Sale Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	5	3
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	16,944	0
available for sale securities, continuous unrealized loss position, 12 months or longer, aggregate loss at end of period	(997)	0
Available for Sale Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	2	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	50,331	31,237
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(2,488)	(406)
Securities held to maturity
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	48,831
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(1,190)
Held to Maturity Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	8
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss at End of Period	0
Held to Maturity Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	48,831
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(1,190)
Residential Collateralized Mortgage-Backed Securities Issued by US Government Sponsored Enterprises
Securities available for sale
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	1,135,151	133,008
Available-for-sale Securities, Continous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(44,775)	(258)
Available for Sale Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	74	9
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	100,530	389
available for sale securities, continuous unrealized loss position, 12 months or longer, aggregate loss at end of period	(7,293)	(2)
Available for Sale Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	7	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	1,235,681	133,397
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(52,068)	(260)
Securities held to maturity
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	1,402,172	17,413
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(82,558)	(16)
Held to Maturity Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	67	1
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss at End of Period	0	0
Held to Maturity Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	1,402,172	17,413
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(82,558)	(16)
Residential Collateralized Mortgage-Backed Securities Issued by Non-US Government Agency
Securities available for sale
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0	0
Available-for-sale Securities, Continous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	0	0
Available for Sale Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	1	2
available for sale securities, continuous unrealized loss position, 12 months or longer, aggregate loss at end of period	0	0
Available for Sale Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	1	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	1	2
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	0	0
Commercial Collateralized Mortgage Backed Securities Issued by US Government Sponsored Enterprises
Securities available for sale
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	43,747	35,316
Available-for-sale Securities, Continous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(2,055)	(138)
Available for Sale Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	6	4
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	2,525	0
available for sale securities, continuous unrealized loss position, 12 months or longer, aggregate loss at end of period	(102)	0
Available for Sale Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	1	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	46,272	35,316
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(2,157)	(138)
Securities held to maturity
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	189,606
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(10,312)
Held to Maturity Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	18
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss at End of Period	0
Held to Maturity Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	189,606
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(10,312)
Collateralized Loan Obligations
Securities available for sale
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	223,458
Available-for-sale Securities, Continous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(4,332)
Available for Sale Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	33
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
available for sale securities, continuous unrealized loss position, 12 months or longer, aggregate loss at end of period	0
Available for Sale Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	223,458
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(4,332)
Corporate bonds
Securities available for sale
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0	0
Available-for-sale Securities, Continous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	0	0
Available for Sale Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	50,644	49,652
available for sale securities, continuous unrealized loss position, 12 months or longer, aggregate loss at end of period	(10,952)	(11,889)
Available for Sale Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	8	8
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	50,644	49,652
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	(10,952)	(11,889)
Securities held to maturity
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	64,541
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss as of Period End	(725)
Held to Maturity Securities in Unrealized Loss Positions Less than Twelve Months Qualitative Disclosure Number of Positions	23
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss at End of Period	0
Held to Maturity Securities in Unrealized Loss Positions Twelve Months or Longer Qualitative Disclosure Number of Positions	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	64,541
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss at End of Period	$ (725)