Commercial Loans Receivables and Allowance for Loan Loss (Concentrations of Commercial Loans Receivables) (Details)	Sep. 29, 2018	Mar. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans Receivable Principal Balance Concentration	18.40%	37.40%
CALIFORNIA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans Receivables Geographic Concentration Percentage	22.10%	14.40%
ARIZONA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans Receivables Geographic Concentration Percentage	13.00%	16.70%
TEXAS
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans Receivables Geographic Concentration Percentage	10.70%	9.00%
OREGON
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans Receivables Geographic Concentration Percentage	10.00%	14.70%