XML 56 R44.htm IDEA: XBRL DOCUMENT

SUPPLEMENTAL OIL AND GAS INFORMATION (UNAUDITED) (Tables)

12 Months Ended

Dec. 31, 2017

Schedule of Oil and Gas Reserve Quantities

Proved Reserves		Natural Gas
(bcf)
Balance at December 31, 2017		429.5
Balance at December 31, 2016		469.8
Balance at December 31, 2015		522.4

- Definition

Tabular disclosure of the net quantities of an enterprise's interests in proved developed and undeveloped reserves of (a) crude oil (including condensate and natural gas liquids), (b) natural gas (including coal bed methane), (c) synthetic oil, (d) synthetic gas, and (e) other nonrenewable natural resources that are intended to be upgraded during the period as of the beginning of the period, changes in quantities during the period, and as of the end of the period.

+ References + Details