Two Harbors Investment Corp. Quarterly report pursuant to Section 13 or 15(d)

Available-for-Sale Securities, at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, at fair value	$ 11,433,195	$ 14,341,102
Available-for-sale Securities Pledged as Collateral	11,399,614	14,159,315
Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, at fair value	2,224,045	2,418,546
Federal National Mortgage Association Certificates and Obligations (FNMA) [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, at fair value	5,150,287	6,768,875
Government National Mortgage Association Certificates and Obligations (GNMA) [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, at fair value	1,651,668	2,104,896
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, at fair value	$ 2,407,195	$ 3,048,785