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Fair Value Measurements - Carrying Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
ASSETS
Securities, at fair value	$ 718,169		$ 784,283
Portfolio loans, net	7,273,870	$ 7,074,928	7,074,928
FHLB and other restricted stock	15,777		22,977
LIABILITIES
Junior subordinated debt securities			64,277
Carrying Value
ASSETS
Cash and due from banks, including interest-bearing deposits	308,489		197,823
Securities, at fair value	718,169		784,283
Loans held for sale	16,724		5,256
Portfolio loans, net	7,273,870		7,074,928
Bank owned life insurance	81,873		80,473
FHLB and other restricted stock	15,777		22,977
Collateral receivable	90,827
Securities held in a deferred compensation plan	5,990		5,987
Mortgage servicing rights	4,717		4,662
LIABILITIES
Deposits	7,633,818		7,036,576
Securities sold under repurchase agreements	42,706		19,888
Short-term borrowings	83,000		281,319
Long-term borrowings	49,076		50,868
Junior subordinated debt securities	64,068		64,277
Carrying Value | Interest rate swaps
ASSETS
Derivative financial assets	90,163		25,647
LIABILITIES
Derivative financial liabilities	90,616		25,615
Carrying Value | Interest rate lock commitments
ASSETS
Derivative financial assets	3,198		321
Carrying Value | Forward sale contracts
ASSETS
Derivative financial assets			1
LIABILITIES
Derivative financial liabilities	450
Fair Value Measurements
ASSETS
Cash and due from banks, including interest-bearing deposits	308,489		197,823
Securities, at fair value	718,169		784,283
Loans held for sale	16,724		5,256
Portfolio loans, net	7,196,845		6,940,875
Bank owned life insurance	81,873		80,473
FHLB and other restricted stock	15,777		22,977
Collateral receivable	90,827
Securities held in a deferred compensation plan	5,990		5,987
Mortgage servicing rights	4,718		4,650
LIABILITIES
Deposits	7,638,132		7,034,595
Securities sold under repurchase agreements	42,706		19,888
Short-term borrowings	83,000		281,319
Long-term borrowings	50,155		51,339
Junior subordinated debt securities	64,068		64,277
Fair Value Measurements | Interest rate swaps
ASSETS
Derivative financial assets	90,163		25,647
LIABILITIES
Derivative financial liabilities	90,616		25,615
Fair Value Measurements | Interest rate lock commitments
ASSETS
Derivative financial assets	3,198		321
Fair Value Measurements | Forward sale contracts
ASSETS
Derivative financial assets			1
LIABILITIES
Derivative financial liabilities	450
Fair Value Measurements | Level 1
ASSETS
Cash and due from banks, including interest-bearing deposits	308,489		197,823
Securities, at fair value	3,185		5,078
Loans held for sale	0		0
Portfolio loans, net	0		0
Bank owned life insurance	0		0
FHLB and other restricted stock	0		0
Collateral receivable	90,827
Securities held in a deferred compensation plan	5,990		5,987
Mortgage servicing rights	0		0
LIABILITIES
Deposits	6,187,722		5,441,143
Securities sold under repurchase agreements	42,706		19,888
Short-term borrowings	83,000		281,319
Long-term borrowings	4,540		4,678
Junior subordinated debt securities	64,068		64,277
Fair Value Measurements | Level 1 | Interest rate swaps
ASSETS
Derivative financial assets	0		0
LIABILITIES
Derivative financial liabilities	0		0
Fair Value Measurements | Level 1 | Interest rate lock commitments
ASSETS
Derivative financial assets	0		0
Fair Value Measurements | Level 1 | Forward sale contracts
ASSETS
Derivative financial assets			0
LIABILITIES
Derivative financial liabilities	0
Fair Value Measurements | Level 2
ASSETS
Cash and due from banks, including interest-bearing deposits	0		0
Securities, at fair value	714,984		779,205
Loans held for sale	0		0
Portfolio loans, net	0		0
Bank owned life insurance	81,873		80,473
FHLB and other restricted stock	0		0
Collateral receivable	0
Securities held in a deferred compensation plan	0		0
Mortgage servicing rights	0		0
LIABILITIES
Deposits	1,450,410		1,593,452
Securities sold under repurchase agreements	0		0
Short-term borrowings	0		0
Long-term borrowings	45,615		46,661
Junior subordinated debt securities	0		0
Fair Value Measurements | Level 2 | Interest rate swaps
ASSETS
Derivative financial assets	90,163		25,647
LIABILITIES
Derivative financial liabilities	90,616		25,615
Fair Value Measurements | Level 2 | Interest rate lock commitments
ASSETS
Derivative financial assets	3,198		321
Fair Value Measurements | Level 2 | Forward sale contracts
ASSETS
Derivative financial assets			1
LIABILITIES
Derivative financial liabilities	450
Fair Value Measurements | Level 3
ASSETS
Cash and due from banks, including interest-bearing deposits	0		0
Securities, at fair value	0		0
Loans held for sale	16,724		5,256
Portfolio loans, net	7,196,845		6,940,875
Bank owned life insurance	0		0
FHLB and other restricted stock	15,777		22,977
Collateral receivable	0
Securities held in a deferred compensation plan	0		0
Mortgage servicing rights	4,718		4,650
LIABILITIES
Deposits	0		0
Securities sold under repurchase agreements	0		0
Short-term borrowings	0		0
Long-term borrowings	0		0
Junior subordinated debt securities	0		0
Fair Value Measurements | Level 3 | Interest rate swaps
ASSETS
Derivative financial assets	0		0
LIABILITIES
Derivative financial liabilities	0		0
Fair Value Measurements | Level 3 | Interest rate lock commitments
ASSETS
Derivative financial assets	0		0
Fair Value Measurements | Level 3 | Forward sale contracts
ASSETS
Derivative financial assets			$ 0
LIABILITIES
Derivative financial liabilities	$ 0

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Debt Securities, Available-for-sale and Equity Securities, FV-NI

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The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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