Basis of Presentation and Significant Accounting Policies Asset Acquisition (Details)	Jul. 31, 2018
Basis of Presentation and Significant Accounting Policies [Abstract]
Agency RMBS, as a percentage of gross assets, acquired in connection with the acquisition of CYS Investments, Inc.	89.00%

Percent of similar identifiable assets of the gross assets acquired in a business combination.

No definition available.

Name:	two_BusinessCombinationPercentofSimilarIdentifiableAssets
Namespace Prefix:	two_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant