Segment Reporting (Policies)	3 Months Ended
Mar. 31, 2018
Segment Reporting [Abstract]
Segment Reporting, Policy [Policy Text Block]	We have two reportable business segments: Single-Family and Multifamily. Results of our two business segments are intended to reflect each segment as if it were a stand-alone business.

Disclosure of accounting policy for segment reporting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790

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