12. Quarterly Results	12 Months Ended
Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Quarterly Results	There were no significant transactions in the fourth quarter of 2017.

The entire disclosure for quarterly financial data. Includes, but is not limited to, tabular presentation of financial information for fiscal quarters, effect of year-end adjustments, and an explanation of matters or transactions that affect comparability of the information.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-URI http://asc.fasb.org/topic&trid=2126967

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