Summary of Significant Accounting Policies - Loans Receivable and Allowance for Loan Losses (Details)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Period of time after which we discontinue accruing interest on loans	90 days
Period of time in non-accrual status for restructured loans to demonstrate performance	6 months
Period after which loans are individually evaluated for impairment	180 days
Length of period one over which the historical loss experience is analyzed	12 months
Length of period two over which the historical loss experience is analyzed	15 months
Length of period three over which the historical loss experience is analyzed	18 months
Length of period four over which the historical loss experience is analyzed	24 months
Minimum length of period over which the historical loss experience is analyzed for a particular loan type that may not have sufficient loss history	2 years
Extended prior period over which loss experience factors are evaluated to consider trends for the majority of loan portfolio	2 years