Derivatives and Hedging Activities (Textual) (Details) - USD ($)		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Derivative [Line Items]
Interest Receivable		$ 32,900,000		$ 32,900,000
Derivative, Net Liability Position, Aggregate Fair Value		96,800,000		$ 96,800,000		$ 26,000,000.0
Maximum Length of Time Hedged in Interest Rate Cash Flow Hedge				4 years 4 months 24 days
Gain (Loss) on Sales of Loans, Net		6,100,000	$ 3,300,000	$ 10,600,000	$ 4,000,000.0
Exposure to Institutional Counterparties		58,800,000		58,800,000		25,400,000
Amortization Of Deferred Hedge Gains Losses		0		0
Customer related positions		153,300,000		153,300,000		51,000,000.0
Fair Value Hedges, Net		0		0		0
Change in Fair Value on Loans Held for Sale		583,000	$ 919,000	839,000	$ 920,000
Interest rate swaps
Derivative [Line Items]
Interest Receivable	[1],[2]	1,100,000		1,100,000		350,000
Derivative, Notional Amount		$ 1,025,000,000		$ 1,025,000,000		925,000,000
Interest Payable, Current	[1],[2]					$ (4,000)
Interest rate collars on loans [Member]
Derivative [Line Items]
Derivative, Average Cap Interest Rate		2.73%		2.73%		2.73%
Derivative, Average Floor Interest Rate		2.20%		2.20%		2.02%
Derivative, Notional Amount		$ 400,000,000		$ 400,000,000		$ 400,000,000
Loan level swaps
Derivative [Line Items]
Interest Receivable	[1],[2]	1,900,000		1,900,000		569,000
Interest Payable, Current	[1],[2]	(2,000,000.0)		(2,000,000.0)		(569,000)
Interest rate swaps on borrowings [Member]
Derivative [Line Items]
Interest Receivable	[1],[2]	177,000		177,000
Derivative, Notional Amount		$ 175,000,000		175,000,000		$ 75,000,000
Interest Income [Member]
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months				(18,400,000)
Interest Expense [Member]
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months				$ 1,200,000

[1] All asset derivatives are located in other assets on the balance sheet.

[2] Approximately $1.1 million and $1.9 million of accrued interest receivable is included in the fair value of the interest rate and loan level asset derivatives, respectively, as of June 30, 2020. Accrued interest receivable of approximately and $350,000 and $569,000 was excluded from the fair value of the interest rate and loan level asset derivatives, respectively, as of December 31, 2019.