Investment Securities (Available For Sale Securities Continuous Unrealized Loss Position Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Schedule Of Available-For-Sale and Held-to-Maturity Securities Table [Line Items]
Investment securities Estimated fair value, Less than 12 months	$ 200,184	$ 90,042
Investment securities Estimated fair value, 12 months or more	30,308	48,322
Investment securities Estimated fair value, Total	230,492	138,364
Investment securities Unrealized losses, Less than 12 months	(962)	(888)
Investment securities Unrealized losses,12 months or more	(254)	(606)
Investment securities Unrealized losses, Total	(1,216)	(1,494)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	5,072	2,788
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	5,072	2,788
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(34)	(7)
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	(34)	(7)
U.S. Agency MBS
Schedule Of Available-For-Sale and Held-to-Maturity Securities Table [Line Items]
Investment securities Estimated fair value, Less than 12 months	50,006	23,630
Investment securities Estimated fair value, 12 months or more	17,058	34,576
Investment securities Estimated fair value, Total	67,064	58,206
Investment securities Unrealized losses, Less than 12 months	(147)	(123)
Investment securities Unrealized losses,12 months or more	(104)	(332)
Investment securities Unrealized losses, Total	(251)	(455)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	5,072	2,063
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	5,072	2,063
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(34)	(5)
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	(34)	(5)
Non-agency MBS
Schedule Of Available-For-Sale and Held-to-Maturity Securities Table [Line Items]
Investment securities Estimated fair value, Less than 12 months	113,432	66,412
Investment securities Estimated fair value, 12 months or more	11,794	12,225
Investment securities Estimated fair value, Total	125,226	78,637
Investment securities Unrealized losses, Less than 12 months	(696)	(765)
Investment securities Unrealized losses,12 months or more	(107)	(251)
Investment securities Unrealized losses, Total	(803)	(1,016)
U.S. Agency asset-backed securities
Schedule Of Available-For-Sale and Held-to-Maturity Securities Table [Line Items]
Investment securities Estimated fair value, Less than 12 months	0	0
Investment securities Estimated fair value, 12 months or more	1,456	1,521
Investment securities Estimated fair value, Total	1,456	1,521
Investment securities Unrealized losses, Less than 12 months	0	0
Investment securities Unrealized losses,12 months or more	(43)	(23)
Investment securities Unrealized losses, Total	(43)	(23)
Corporate Debt Securities
Schedule Of Available-For-Sale and Held-to-Maturity Securities Table [Line Items]
Investment securities Estimated fair value, Less than 12 months	36,746
Investment securities Estimated fair value, 12 months or more	0
Investment securities Estimated fair value, Total	36,746
Investment securities Unrealized losses, Less than 12 months	(119)
Investment securities Unrealized losses,12 months or more	0
Investment securities Unrealized losses, Total	(119)
Obligations of state and political subdivisions
Schedule Of Available-For-Sale and Held-to-Maturity Securities Table [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0	725
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	0	725
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(2)
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 0	$ (2)

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

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