Quarterly report pursuant to Section 13 or 15(d)

Schedule of Available-for-sale Securities Reconciliation, Non-Agency Unamortized Net Discount and Designated Credit Reserves (Details)

v3.7.0.1
Schedule of Available-for-sale Securities Reconciliation, Non-Agency Unamortized Net Discount and Designated Credit Reserves (Details) - Mortgage-backed Securities, Issued by Private Enterprises [Member] - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Available-for-sale Securities, Designated Credit Reserve [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Unamortized Discount, Beginning Balance $ 367,437 $ 409,077
Available-for-sale Securities, Unamortized Discount, Acquisitions 88,719 (1,013)
Available-for-sale Securities, Unamortized Discount, Accretion 0 0
Available-for-sale Securities, Unamortized Discount, Credit Losses (4,546) (3,093)
Available-for-sale Securities, Unamortized Discount, Other-than-temporary Impairment Adjustment 0 121
Available-for-sale Securities, Unamortized Discount, Transfers (8,754) (19,454)
Available-for-sale Securities, Unamortized Discount, Sales, Calls and Other 0 (32,562)
Available-for-sale Securities, Unamortized Discount, Ending Balance 442,856 353,076
Available-for-sale Securities, Net, Unamortized [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Unamortized Discount, Beginning Balance 808,975 707,021
Available-for-sale Securities, Unamortized Discount, Acquisitions 71,471 25,222
Available-for-sale Securities, Unamortized Discount, Accretion (22,183) (16,760)
Available-for-sale Securities, Unamortized Discount, Credit Losses 0 0
Available-for-sale Securities, Unamortized Discount, Other-than-temporary Impairment Adjustment 0 0
Available-for-sale Securities, Unamortized Discount, Transfers 8,754 19,454
Available-for-sale Securities, Unamortized Discount, Sales, Calls and Other (30,676) (55,535)
Available-for-sale Securities, Unamortized Discount, Ending Balance 836,341 679,402
Available-for-sale Securities, Unamortized Discount [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Unamortized Discount, Beginning Balance 1,176,412 1,116,098
Available-for-sale Securities, Unamortized Discount, Acquisitions 160,190 24,209
Available-for-sale Securities, Unamortized Discount, Accretion (22,183) (16,760)
Available-for-sale Securities, Unamortized Discount, Credit Losses (4,546) (3,093)
Available-for-sale Securities, Unamortized Discount, Other-than-temporary Impairment Adjustment 0 121
Available-for-sale Securities, Unamortized Discount, Transfers 0 0
Available-for-sale Securities, Unamortized Discount, Sales, Calls and Other (30,676) (88,097)
Available-for-sale Securities, Unamortized Discount, Ending Balance $ 1,279,197 $ 1,032,478