Fair Value Measurement and Fair Value of Financial Instruments (Carrying Amounts of Assets That Were Still Held and Had Fair Value Changes Measured on a Nonrecurring Basis) (Details) - Fair Value, Measurements, Nonrecurring - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	$ 43,851	$ 32,858
Non-PCI impaired loans | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	0	0
Non-PCI impaired loans | Significant Other Observable Inputs (Level 2)
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	0	0
Non-PCI impaired loans | Significant Unobservable Inputs (Level 3)
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	43,851	32,858
Non-PCI impaired loans | Commercial and industrial (“C&I”) | Commercial lending
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	43,087	26,873
Non-PCI impaired loans | Commercial and industrial (“C&I”) | Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial lending
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	0	0
Non-PCI impaired loans | Commercial and industrial (“C&I”) | Significant Other Observable Inputs (Level 2) | Commercial lending
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	0	0
Non-PCI impaired loans | Commercial and industrial (“C&I”) | Significant Unobservable Inputs (Level 3) | Commercial lending
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	43,087	26,873
Non-PCI impaired loans | Commercial real estate (“CRE”) | Commercial lending
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	764	3,434
Non-PCI impaired loans | Commercial real estate (“CRE”) | Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial lending
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	0	0
Non-PCI impaired loans | Commercial real estate (“CRE”) | Significant Other Observable Inputs (Level 2) | Commercial lending
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	0	0
Non-PCI impaired loans | Commercial real estate (“CRE”) | Significant Unobservable Inputs (Level 3) | Commercial lending
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans	764	3,434
Non-PCI impaired loans | Real estate loan | Consumer lending | Single-family residential
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans		2,551
Non-PCI impaired loans | Real estate loan | Quoted Prices in Active Markets for Identical Assets (Level 1) | Consumer lending | Single-family residential
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans		0
Non-PCI impaired loans | Real estate loan | Significant Other Observable Inputs (Level 2) | Consumer lending | Single-family residential
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans		0
Non-PCI impaired loans | Real estate loan | Significant Unobservable Inputs (Level 3) | Consumer lending | Single-family residential
Fair Value, Assets Measured on a Nonrecurring Basis
Non-PCI impaired loans		$ 2,551
OREO
Fair Value, Assets Measured on a Nonrecurring Basis
OREO	590
OREO | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets Measured on a Nonrecurring Basis
OREO	0
OREO | Significant Other Observable Inputs (Level 2)
Fair Value, Assets Measured on a Nonrecurring Basis
OREO	0
OREO | Significant Unobservable Inputs (Level 3)
Fair Value, Assets Measured on a Nonrecurring Basis
OREO	590
Investments in tax credit and other investments, net
Fair Value, Assets Measured on a Nonrecurring Basis
OREO	830
Investments in tax credit and other investments, net | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets Measured on a Nonrecurring Basis
OREO	0
Investments in tax credit and other investments, net | Significant Other Observable Inputs (Level 2)
Fair Value, Assets Measured on a Nonrecurring Basis
OREO	0
Investments in tax credit and other investments, net | Significant Unobservable Inputs (Level 3)
Fair Value, Assets Measured on a Nonrecurring Basis
OREO	$ 830