Fair Value Measurements Financial Instruments, Quantitative Information (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Time deposits [Member]
Fair Value Inputs, Financial Instruments, Quantitative Information [Line Items]
Contractual Yield, Minimum	0.03%	0.02%	0.02%
Contractual Yield, Maximum	10.00%	10.00%	9.65%
Repricing (in years)	1 year 329 days	2 years 18 days	1 year 350 days
Discount Rate, Minimum	1.67%	1.15%	1.57%
Discount Rate, Maximum	2.09%	1.47%	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	3.42%	0.80%	3.50%
Repricing (in years)	7 days	1 day	1 day
Discount Rate, Minimum	0.82%	0.25%	0.55%
Discount Rate, Maximum	3.44%	2.89%	3.22%
Subordinated debentures [Member]
Fair Value Inputs, Financial Instruments, Quantitative Information [Line Items]
Contractual Yield, Minimum	5.38%	1.31%	5.38%
Contractual Yield, Maximum	5.38%	1.31%	5.38%
Repricing (in years)	16 years 259 days	1 year 44 days	16 years 314 days
Discount Rate, Minimum	5.54%	2.13%	6.11%
Discount Rate, Maximum	5.54%	2.13%	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)	245 days	267 days	256 days
Discount Rate, Minimum	0.62%	0.46%	0.64%
Discount Rate, Maximum	4.68%	3.92%	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)	266 days	263 days	259 days
Discount Rate, Minimum	1.00%	0.85%	0.94%
Discount Rate, Maximum	4.37%	3.60%	4.27%
Residential mortgage | Loans Receivable [Member]
Fair Value Inputs, Financial Instruments, Quantitative Information [Line Items]
Contractual Yield, Minimum	1.74%	1.68%	1.74%
Contractual Yield, Maximum	18.00%	18.00%	18.00%
Repricing (in years)	2 years 95 days	2 years 26 days	2 years 99 days
Discount Rate, Minimum	1.83%	1.23%	1.71%
Discount Rate, Maximum	4.26%	3.73%	4.26%
Personal | Loans Receivable [Member]
Fair Value Inputs, Financial Instruments, Quantitative Information [Line Items]
Contractual Yield, Minimum	0.25%	0.38%	0.25%
Contractual Yield, Maximum	21.00%	21.00%	21.00%
Repricing (in years)	110 days	135 days	146 days
Discount Rate, Minimum	0.77%	0.78%	1.03%
Discount Rate, Maximum	4.71%	4.01%	4.59%