Fair Value Measurement and Fair Value of Financial Instruments (Fair Value Adjustments of Assets Measured on a Nonrecurring Basis) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets		$ (8)		$ 61
Fair Value, Measurements, Nonrecurring | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	$ 4,537	(13,873)	$ 514	(11,371)
Fair Value, Measurements, Nonrecurring | OREO non-recurring fair value losses
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	0	0	0	(285)
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	4,544	(14,060)	595	(11,418)
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	66	193	(23)	118
Fair Value, Measurements, Nonrecurring | Commercial lending | Real estate loan | Multifamily | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	0	(106)	0	(107)
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)
Fair Value, Measurements, Nonrecurring | Consumer lending | Real estate loan | Single-family | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	0	76	15	158
Fair Value, Measurements, Nonrecurring | Consumer lending | HELOCs | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	$ (73)	$ 24	$ (73)	$ 25