Fair Value Measurement and Fair Value of Financial Instruments (Fair Value Adjustments of Assets Measured on a Nonrecurring Basis) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	$ 0	$ 0	$ 0	$ 61,000
Fair Value, Measurements, Nonrecurring | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	(8,646,000)	(16,951,000)	(7,390,000)	(17,640,000)
Fair Value, Measurements, Nonrecurring | OREO nonrecurring fair value losses
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	0	(285,000)	0	(286,000)
Fair Value, Measurements, Nonrecurring | Commercial lending | Commercial and industrial (“C&I”) | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	(8,508,000)	(16,954,000)	(7,204,000)	(17,648,000)
Fair Value, Measurements, Nonrecurring | Commercial lending | Commercial real estate (“CRE”) | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	50,000	6,000	61,000	81,000
Fair Value, Measurements, Nonrecurring | Commercial lending | Real estate loan | Multifamily residential | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	0	(6,000)	0	(112,000)
Fair Value, Measurements, Nonrecurring | Commercial lending | Construction and land | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	0	0	0	(147,000)
Fair Value, Measurements, Nonrecurring | Consumer lending | Real estate loan | Single-family residential | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	0	3,000	15,000	161,000
Fair Value, Measurements, Nonrecurring | Consumer lending | HELOCs | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	$ (188,000)	$ 0	$ (262,000)	$ 25,000