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
 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Available-for-sale Securities, Designated Credit Reserve [Member]    
Available-for-sale Securities, Unamortized Discount [Roll Forward]    
Unamortized discount on available-for-sale securities, beginning balance $ (367,437) $ (409,077)
Acquisitions (100,558) (16,217)
Accretion of net discount 0 0
Realized credit losses 8,424 (2,371)
Reclassification adjustment for other-than-temporary impairments (429) (211)
Transfers from (to) 22,676 59,453
Sales, calls, other 3,588 32,562
Unamortized discount on available-for-sale securities, ending balance (433,736) (335,861)
Available-for-sale Securities, Net, Unamortized [Member]    
Available-for-sale Securities, Unamortized Discount [Roll Forward]    
Unamortized discount on available-for-sale securities, beginning balance (808,975) (707,021)
Acquisitions (88,807) (74,039)
Accretion of net discount 44,301 32,287
Realized credit losses 0 0
Reclassification adjustment for other-than-temporary impairments 0 0
Transfers from (to) (22,676) (59,453)
Sales, calls, other 69,893 67,121
Unamortized discount on available-for-sale securities, ending balance (806,264) (741,105)
Available-for-sale Securities, Unamortized Discount [Member]    
Available-for-sale Securities, Unamortized Discount [Roll Forward]    
Unamortized discount on available-for-sale securities, beginning balance (1,176,412) (1,116,098)
Acquisitions (189,365) (90,256)
Accretion of net discount 44,301 32,287
Realized credit losses 8,424 (2,371)
Reclassification adjustment for other-than-temporary impairments (429) (211)
Transfers from (to) 0 0
Sales, calls, other 73,481 99,683
Unamortized discount on available-for-sale securities, ending balance $ (1,240,000) $ (1,076,966)