Accrued Interest Receivable Schedule of Accounts, Notes, Loans and Financing Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	$ 56,250	$ 65,529
Loans Held-for-sale, Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	3,014	1,997
Loans Held-for-investment, Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	16,016	10,197
Loans Held-for-investment, Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	626	0
US Treasury Securities [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	0	8,084
Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	7,767	8,734
Federal National Mortgage Association Certificates and Obligations (FNMA) [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	17,117	22,392
Government National Mortgage Association Certificates and Obligations (GNMA) [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	8,483	10,290
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	3,227	3,835
Available-for-sale Securities [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	$ 36,594	$ 45,251