Fair Value Qualitative information about Level 3 fair value measurements (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	$ 5,113,869	$ 5,014,285
Impaired Loan Fair Value	7,876	9,496
Other Assets, Fair Value Disclosure	5,090,488	4,997,318
Loans Held-for-sale, Fair Value Disclosure	15,204	7,306
Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	5,098,364	5,006,814
Impaired Loan Fair Value	7,876	9,496
Other Assets, Fair Value Disclosure	5,090,488	4,997,318
Fair Value, Measurements, Nonrecurring [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	7,876	9,496
Other Assets, Fair Value Disclosure	7,727	8,515
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	7,876	9,496
Other Assets, Fair Value Disclosure	7,727	8,515
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other Assets, Fair Value Disclosure	3,348	3,387
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other Assets, Fair Value Disclosure	3,348	3,387
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	3,374	3,698
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	$ 3,374	3,698
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Loans Receivable [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired Loan Fair Value		$ 3,698
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Loans Receivable [Member] | Minimum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	0.00%	0.00%
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Loans Receivable [Member] | Minimum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Cap Rate	7.00%	7.00%
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Loans Receivable [Member] | Minimum [Member] | Cost Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Accumulated Depreciation	17.00%	50.00%
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Loans Receivable [Member] | Maximum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	90.00%	45.90%
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Loans Receivable [Member] | Maximum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Cap Rate	11.00%	13.30%
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Loans Receivable [Member] | Maximum [Member] | Cost Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Accumulated Depreciation	50.00%	50.00%
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Loans Receivable [Member] | Weighted Average [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	21.90%	20.30%
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Loans Receivable [Member] | Weighted Average [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Cap Rate	10.10%	9.50%
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Loans Receivable [Member] | Weighted Average [Member] | Cost Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Accumulated Depreciation	38.20%	50.00%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate, SEPH Commercial Land and Development [Member] | Loans Receivable [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired Loan Fair Value		$ 2,044
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate, SEPH Commercial Land and Development [Member] | Loans Receivable [Member] | Minimum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	5.00%	5.00%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate, SEPH Commercial Land and Development [Member] | Loans Receivable [Member] | Minimum [Member] | Bulk Sale Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate		10.70%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate, SEPH Commercial Land and Development [Member] | Loans Receivable [Member] | Maximum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	40.00%	40.00%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate, SEPH Commercial Land and Development [Member] | Loans Receivable [Member] | Maximum [Member] | Bulk Sale Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate		10.70%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate, SEPH Commercial Land and Development [Member] | Loans Receivable [Member] | Weighted Average [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	22.50%	22.10%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate, SEPH Commercial Land and Development [Member] | Loans Receivable [Member] | Weighted Average [Member] | Bulk Sale Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate		10.70%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate - Remaining Commercial [Member] | Loans Receivable [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired Loan Fair Value		$ 1,872
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate - Remaining Commercial [Member] | Loans Receivable [Member] | Minimum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	0.00%	0.00%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate - Remaining Commercial [Member] | Loans Receivable [Member] | Minimum [Member] | Bulk Sale Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	10.00%	10.00%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate - Remaining Commercial [Member] | Loans Receivable [Member] | Maximum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	15.60%	25.30%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate - Remaining Commercial [Member] | Loans Receivable [Member] | Maximum [Member] | Bulk Sale Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	10.00%	10.70%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate - Remaining Commercial [Member] | Loans Receivable [Member] | Weighted Average [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	1.60%	1.00%
Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate - Remaining Commercial [Member] | Loans Receivable [Member] | Weighted Average [Member] | Bulk Sale Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	10.00%	10.00%
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other Assets, Fair Value Disclosure	$ 1,254	$ 2,332
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other Assets, Fair Value Disclosure	$ 1,254	2,332
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Loans Receivable [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired Loan Fair Value		$ 1,882
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Loans Receivable [Member] | Minimum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	0.00%	0.00%
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Loans Receivable [Member] | Minimum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Cap Rate	10.00%	3.80%
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Loans Receivable [Member] | Minimum [Member] | Cost Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Accumulated Depreciation	50.00%	33.30%
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Loans Receivable [Member] | Maximum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	110.00%	96.70%
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Loans Receivable [Member] | Maximum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Cap Rate	10.00%	10.10%
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Loans Receivable [Member] | Maximum [Member] | Cost Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Accumulated Depreciation	50.00%	50.00%
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Loans Receivable [Member] | Weighted Average [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	15.40%	12.50%
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Loans Receivable [Member] | Weighted Average [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Cap Rate	10.00%	9.10%
Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Loans Receivable [Member] | Weighted Average [Member] | Cost Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Accumulated Depreciation	50.00%	43.40%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Commercial [Member] | Minimum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	0.00%	2.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Commercial [Member] | Minimum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Cap Rate	9.50%	9.50%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Commercial [Member] | Maximum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	69.00%	71.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Commercial [Member] | Maximum [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Cap Rate	14.00%	9.50%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Commercial [Member] | Real Estate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other Assets, Fair Value Disclosure	$ 3,125	$ 2,796
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Commercial [Member] | Real Estate [Member] | Weighted Average [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	23.00%	26.90%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Commercial [Member] | Real Estate [Member] | Weighted Average [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Cap Rate	9.90%	9.50%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Construction [Member] | Minimum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	0.00%	0.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Construction [Member] | Minimum [Member] | Bulk Sale Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	15.00%	15.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Construction [Member] | Maximum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	85.00%	85.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Construction [Member] | Maximum [Member] | Bulk Sale Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	15.00%	15.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Construction [Member] | Real Estate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other Assets, Fair Value Disclosure	$ 3,348	$ 3,387
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Construction [Member] | Real Estate [Member] | Weighted Average [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	27.40%	24.30%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Construction [Member] | Real Estate [Member] | Weighted Average [Member] | Bulk Sale Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	15.00%	15.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Residential [Member] | Minimum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	2.80%	0.10%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Residential [Member] | Maximum [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	61.80%	61.80%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Residential [Member] | Real Estate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other Assets, Fair Value Disclosure	$ 1,254	$ 2,332
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate Owned, Residential [Member] | Real Estate [Member] | Weighted Average [Member] | Sales Comparison Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Comparability Adjustments	30.20%	23.00%
Construction Real Estate, SEPH Commercial Land and Development [Member] | Fair Value, Measurements, Nonrecurring [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	$ 1,700	$ 2,044
Construction Real Estate, SEPH Commercial Land and Development [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	1,700	2,044
Construction Real Estate - Remaining Commercial [Member] | Fair Value, Measurements, Nonrecurring [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	861	1,872
Construction Real Estate - Remaining Commercial [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	861	1,872
Fair Value [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired Loan Fair Value		$ 9,496
Fair Value [Member] | Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	3,374
Fair Value [Member] | Fair Value, Measurements, Nonrecurring [Member] | Residential Real Estate [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	1,941
Fair Value [Member] | Construction Real Estate, SEPH Commercial Land and Development [Member] | Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	1,700
Fair Value [Member] | Construction Real Estate - Remaining Commercial [Member] | Fair Value, Measurements, Nonrecurring [Member] | Construction Real Estate [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	$ 861