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

Schedule of Underlying Assets of Repurchase Agreements when Amount of Repurchase Agreements Exceeds 10 Percent of Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Assets Sold under Agreements to Repurchase [Line Items]
Assets Sold under Agreements to Repurchase, Market Value	$ 15,337,798	$ 10,753,868
Available-for-sale Securities [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Assets Sold under Agreements to Repurchase, Market Value	14,053,024	9,540,849
Commercial Real Estate Assets [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Assets Sold under Agreements to Repurchase, Market Value	756,771	648,885
Retained Interest [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Assets Sold under Agreements to Repurchase, Market Value	215,492	211,095
Cash and Cash Equivalents [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Assets Sold under Agreements to Repurchase, Market Value	15,000	15,000
Restricted Cash and Cash Equivalents [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Assets Sold under Agreements to Repurchase, Market Value	134,853	162,759
Due From Correspondent Brokers [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Assets Sold under Agreements to Repurchase, Market Value	49,671	48,939
Derivative Financial Instruments, Assets [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Assets Sold under Agreements to Repurchase, Market Value	$ 112,987	$ 126,341