Securities Securities (Available for sale securities in continuous unrealized loss position) (Details) $ in Thousands	Mar. 31, 2021 USD ($) holding	Dec. 31, 2020 USD ($) holding
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	15	7
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 221,563	$ 24,248
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(6,153)	(89)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,552	1,056
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(349)	(373)
Debt Securities, Available-for-sale, Unrealized Loss Position	223,115	25,304
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 6,502	$ 462
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	8	3
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 98,873	$ 437
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3,898)	(1)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Unrealized Loss Position	98,873	437
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 3,898	$ 1
Collateralized Debt Obligations [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	1	2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 9,519	$ 23,323
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(11)	(87)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Unrealized Loss Position	9,519	23,323
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 11	$ 87
Single issuer trust preferred securities issued by banks and insurers
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	1	1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	$ 488
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(1)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	488	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1)	0
Debt Securities, Available-for-sale, Unrealized Loss Position	488	488
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 1	$ 1
Pooled trust preferred securities issued by banks and insurers
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	1	1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	$ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,064	1,056
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(348)	(373)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,064	1,056
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 348	$ 373
U.S. government agency securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions \| holding	4
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 113,171
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(2,244)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Debt Securities, Available-for-sale, Unrealized Loss Position	113,171
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 2,244

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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