Securities Securities (Reconciliation of amortized cost of held to maturity securities) (Details) $ in Thousands	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($) holding
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	$ 777,798	$ 740,806
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	31,700	13,428
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(143)	(971)
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0
Debt Securities, Held-to-maturity, Fair Value	809,355	753,263
Small Business Administration Pooled Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Fair Value		7,349
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Aggregate Loss		55
Debt Securities, Held-to-maturity	30,716	31,324
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	745	338
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	(55)
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0
Debt Securities, Held-to-maturity, Fair Value	31,461	$ 31,607
Available for Sale and Held to Maturity Securities in Unrealized Loss Positions Qualitative Disclosure Number of Positions | holding		1
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Less than Twelve Months Fair Value		$ 7,349
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months		(55)
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Twelve Months or Longer Fair Value		0
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months		0
Trust Preferred Securities Subject to Mandatory Redemption [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	1,500	1,500
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(10)	(10)
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0
Debt Securities, Held-to-maturity, Fair Value	1,490	1,490
Collateralized Debt Obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Fair Value		85,858
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Aggregate Loss		868
Debt Securities, Held-to-maturity	277,921	293,662
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	11,981	4,501
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	(849)
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0
Debt Securities, Held-to-maturity, Fair Value	289,902	$ 297,314
Available for Sale and Held to Maturity Securities in Unrealized Loss Positions Qualitative Disclosure Number of Positions | holding		17
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Less than Twelve Months Fair Value		$ 48,476
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months		(215)
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Twelve Months or Longer Fair Value		37,382
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months		653
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Fair Value		34,252
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Aggregate Loss		61
Debt Securities, Held-to-maturity	463,632	397,414
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	18,864	8,445
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(133)	(57)
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0
Debt Securities, Held-to-maturity, Fair Value	482,363	$ 405,802
Available for Sale and Held to Maturity Securities in Unrealized Loss Positions Qualitative Disclosure Number of Positions | holding		12
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Less than Twelve Months Fair Value		$ 34,009
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months		(59)
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Twelve Months or Longer Fair Value		243
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months		2
US Treasury Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	4,029	4,032
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	110	21
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0
Debt Securities, Held-to-maturity, Fair Value	4,139	4,053
U.S. government agency securities
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	0	12,874
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain		123
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0
Debt Securities, Held-to-maturity, Fair Value	$ 0	12,997
Equity Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Fair Value		130,063
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Aggregate Loss		$ 1,368
Available for Sale and Held to Maturity Securities in Unrealized Loss Positions Qualitative Disclosure Number of Positions | holding		32
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Less than Twelve Months Fair Value		$ 89,834
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months		(329)
Available for Sale and Held to Maturity Securities Continuous Unrealized Loss Position Twelve Months or Longer Fair Value		40,229
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months		$ 1,039