Loans, Additional Information (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2014 Maximum Commercial Secured By Real Estate [Member]	Jun. 30, 2014 Maximum Residential Real Estate [Member]	Jun. 30, 2014 Maximum Consumer [Member]	Jun. 30, 2014 Minimum Commercial Secured By Real Estate [Member]	Jun. 30, 2014 Minimum Residential Real Estate [Member]	Jun. 30, 2014 Collateralized Mortgage Backed Securities [Member]	Dec. 31, 2013 Collateralized Mortgage Backed Securities [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Pledged financial instruments, securities for federal home loan bank						$ 203	$ 183
Amortization period	25 years	30 years	72 months	5 years	5 years
Balloon payments period	10 years			1 year
Adjustable rate period	10 years			1 year
Maximum loan to appraised value ratio	75.00%				80.00%
Home equity line of credit draw period		5 years