Fair Value Measurement and Fair Value of Financial Instruments (Details 5) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Loans held-for-sale
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	$ 0	$ 0	$ 61,000	$ 2,400,000
Fair Value, Measurements, Nonrecurring | Non-PCI impaired loans
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	(16,951,000)	(219,000)	(17,640,000)	(3,753,000)
Fair Value, Measurements, Nonrecurring | Non-PCI impaired loans | CRE
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	6,000	(282,000)	(66,000)	1,741,000
Fair Value, Measurements, Nonrecurring | Non-PCI impaired loans | C&I
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	(16,954,000)	77,000	(17,648,000)	(5,497,000)
Fair Value, Measurements, Nonrecurring | Non-PCI impaired loans | Residential
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	(3,000)	(14,000)	49,000	(14,000)
Fair Value, Measurements, Nonrecurring | Non-PCI impaired loans | Consumer
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	0	0	25,000	17,000
Fair Value, Measurements, Nonrecurring | OREO
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	(285,000)	(41,000)	(286,000)	(994,000)
Fair Value, Measurements, Nonrecurring | Loans held-for-sale
Fair Value, Assets Measured on a Nonrecurring Basis
Fair value adjustments of assets	$ 0	$ 0	$ 0	$ (2,351,000)