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

Serviced Mortgage Assets (Details) $ in Thousands	Sep. 30, 2018 USD ($) loan	Dec. 31, 2017 USD ($) loan
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Number of Loans \| loan	585,563	458,133
Unpaid Principal Balance \| $	$ 133,592,693	$ 104,002,292
Servicing Contracts [Member]
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Number of Loans \| loan	581,677	454,028
Unpaid Principal Balance \| $	$ 131,114,538	$ 101,344,054
Loans in Securitization Trusts, Residential Mortgages [Member]
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Number of Loans \| loan	3,663	3,845
Unpaid Principal Balance \| $	$ 2,443,368	$ 2,618,016
Loans Held-for-Sale, Residential Mortgages [Member]
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Number of Loans \| loan	206	236
Unpaid Principal Balance \| $	$ 33,448	$ 37,632
Other Assets [Member]
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Number of Loans \| loan	17	24
Unpaid Principal Balance \| $	$ 1,339	$ 2,590