TWO Annual report pursuant to Section 13 and 15(d)

Schedule of Repurchase Agreements by Maturity (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	$ 12,932,463	$ 12,250,450
Maturity up to 30 days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	3,979,317	3,831,917
Maturity 30 to 59 Days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	4,595,425	2,013,733
Maturity 60 to 89 Days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	903,286	2,225,967
Maturity 90 to 119 Days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	434,550	1,386,371
Maturity 120 to 364 days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	1,929,164	1,594,962
Maturity on Demand [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	997,500	997,500
Maturity Over One Year [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	$ 93,221	$ 200,000