TWO Quarterly report pursuant to Section 13 or 15(d)

Available-for-sale Securities, Rollforward of the Allowance for Credit Losses (Details)

Available-for-sale Securities, Rollforward of the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses at beginning of period	$ (42,583)	$ 0
Additions on securities for which credit losses were not previously recorded	(86)	(44,286)
Additions arising from purchases of securities accounted for as purchased credit deteriorated	0	0
Reductions for securities sold	0	246,792
Reductions due to the intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost	0	0
Increase (decrease) on securities with previously recorded credit losses	(7,014)	(9,645)
Writeoffs	24,188	29,055
Recoveries of amounts previously written off	0	(2,535)
Allowance for credit losses at end of period	(25,495)	(25,495)
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses at beginning of period	30,634
Additions on securities for which credit losses were not previously recorded	86	32,882
Additions arising from purchases of securities accounted for as purchased credit deteriorated	0	0
Reductions for securities sold	0	0
Reductions due to the intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost	0	0
Increase (decrease) on securities with previously recorded credit losses	558	(1,604)
Writeoffs	(12,037)	(12,037)
Recoveries of amounts previously written off	0	0
Allowance for credit losses at end of period	(19,241)	(19,241)
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses at beginning of period	11,949
Additions on securities for which credit losses were not previously recorded	0	11,404
Additions arising from purchases of securities accounted for as purchased credit deteriorated	0	0
Reductions for securities sold	0	(246,792)
Reductions due to the intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost	0	0
Increase (decrease) on securities with previously recorded credit losses	6,456	11,249
Writeoffs	(12,151)	(17,018)
Recoveries of amounts previously written off	0	2,535
Allowance for credit losses at end of period	$ (6,254)	$ (6,254)