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

Trading Securities, at Fair Value (Notes)	6 Months Ended
Trading Securities, at Fair Value (Notes)	Jun. 30, 2013
Trading Securities, at Fair Value [Abstract]
Trading Securities, at Fair Value	Trading Securities, at Fair Value The Company holds U.S. Treasuries in a taxable REIT subsidiary and classifies these securities as trading instruments due to short-term investment objectives. As of June 30, 2013 and December 31, 2012, the Company held U.S. Treasuries with an amortized cost of $1.0 billion and a fair value of $1.0 billion for both periods classified as trading securities. The unrealized gains included within trading securities were $3.5 million and $5.0 million as of June 30, 2013 and December 31, 2012, respectively. The Company did not sell any trading securities during the three and six months ended June 30, 2013. For both the three and six months ended June 30, 2013, trading securities experienced change in unrealized losses of $1.6 million. Unrealized gains and losses are recorded as a component of gains on investment securities in the Company's condensed consolidated statements of comprehensive (loss) income. At June 30, 2013, the Company pledged trading securities with a carrying value of $1.0 billion as collateral for repurchase agreements. See Note 16 - Repurchase Agreements.