Fair Value Measurements Financial Instruments, Quantitative Information (Details)	6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Time deposits [Member]
Fair Value Inputs, Financial Instruments, Quantitative Information [Line Items]
Contractual Yield, Minimum	0.03%	0.03%	0.02%
Contractual Yield, Maximum	10.00%	9.64%	9.65%
Repricing (in years)	1 year 332 days	2 years 55 days	1 year 350 days
Discount Rate, Minimum	1.81%	1.16%	1.57%
Discount Rate, Maximum	2.12%	1.43%	2.00%
Other borrowings [Member]
Fair Value Inputs, Financial Instruments, Quantitative Information [Line Items]
Contractual Yield, Minimum	0.25%	0.25%	0.25%
Contractual Yield, Maximum	3.58%	3.28%	3.50%
Repricing (in years)	7 days	7 days	1 day
Discount Rate, Minimum	1.06%	0.30%	0.55%
Discount Rate, Maximum	3.69%	2.92%	3.22%
Subordinated debentures [Member]
Fair Value Inputs, Financial Instruments, Quantitative Information [Line Items]
Contractual Yield, Minimum	5.38%	1.32%	5.38%
Contractual Yield, Maximum	5.38%	5.38%	5.38%
Repricing (in years)	16 years 329 days	8 years 128 days	16 years 314 days
Discount Rate, Minimum	4.89%	2.16%	6.11%
Discount Rate, Maximum	4.89%	5.38%	6.11%
Commercial | Loans Receivable [Member]
Fair Value Inputs, Financial Instruments, Quantitative Information [Line Items]
Contractual Yield, Minimum	0.38%	0.38%	0.38%
Contractual Yield, Maximum	30.00%	30.00%	30.00%
Repricing (in years)	234 days	252 days	256 days
Discount Rate, Minimum	0.71%	0.55%	0.64%
Discount Rate, Maximum	4.56%	3.68%	4.60%
Commercial real estate | Loans Receivable [Member]
Fair Value Inputs, Financial Instruments, Quantitative Information [Line Items]
Contractual Yield, Minimum	0.38%	0.38%	0.38%
Contractual Yield, Maximum	18.00%	18.00%	18.00%
Repricing (in years)	281 days	266 days	259 days
Discount Rate, Minimum	1.03%	0.80%	0.94%
Discount Rate, Maximum	4.31%	3.65%	4.27%
Residential mortgage | Loans Receivable [Member]
Fair Value Inputs, Financial Instruments, Quantitative Information [Line Items]
Contractual Yield, Minimum	1.74%	1.70%	1.74%
Contractual Yield, Maximum	18.00%	18.00%	18.00%
Repricing (in years)	2 years 66 days	1 year 354 days	2 years 99 days
Discount Rate, Minimum	1.75%	1.25%	1.71%
Discount Rate, Maximum	4.19%	3.75%	4.26%
Personal | Loans Receivable [Member]
Fair Value Inputs, Financial Instruments, Quantitative Information [Line Items]
Contractual Yield, Minimum	0.25%	0.25%	0.25%
Contractual Yield, Maximum	21.00%	21.00%	21.00%
Repricing (in years)	102 days	128 days	146 days
Discount Rate, Minimum	0.70%	0.71%	1.03%
Discount Rate, Maximum	4.68%	3.91%	4.59%