Loans (Loans by FICO Score, Consumer) (Details)		Mar. 31, 2017	Dec. 31, 2016
HELOC [Member] | FICO score 740 or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		57.60%	56.90%
HELOC [Member] | FICO score 720-739
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		8.80%	8.80%
HELOC [Member] | FICO score 700-719
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		8.20%	8.60%
HELOC [Member] | FICO score 660-699
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		12.60%	13.20%
HELOC [Member] | FICO score 620-659
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		5.70%	5.60%
HELOC [Member] | FICO score less than 620
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage	[1]	7.10%	6.90%
HELOC [Member] | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		100.00%	100.00%
R/E Installment Loans [Member] | FICO score 740 or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		70.10%	70.30%
R/E Installment Loans [Member] | FICO score 720-739
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		8.00%	8.30%
R/E Installment Loans [Member] | FICO score 700-719
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		7.20%	6.80%
R/E Installment Loans [Member] | FICO score 660-699
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		9.00%	8.40%
R/E Installment Loans [Member] | FICO score 620-659
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		3.00%	3.50%
R/E Installment Loans [Member] | FICO score less than 620
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage	[1]	2.70%	2.70%
R/E Installment Loans [Member] | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		100.00%	100.00%
Permanent Mortgage Portfolio Segment | FICO score 740 or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		45.50%	45.00%
Permanent Mortgage Portfolio Segment | FICO score 720-739
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		8.70%	9.50%
Permanent Mortgage Portfolio Segment | FICO score 700-719
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		9.50%	9.20%
Permanent Mortgage Portfolio Segment | FICO score 660-699
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		16.80%	17.10%
Permanent Mortgage Portfolio Segment | FICO score 620-659
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		8.90%	9.10%
Permanent Mortgage Portfolio Segment | FICO score less than 620
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage	[1]	10.60%	10.10%
Permanent Mortgage Portfolio Segment | Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average refreshed FICO score percentage		100.00%	100.00%

[1] For this group, a majority of the loan balances had FICO scores at the time of the origination that exceeded 620 but have since deteriorated as the loans have seasoned .