2.2.0.25falsefalse006060 - Disclosure - GAS IN STORAGEtruefalsefalse1falsefalseUSDfalsefalse1/1/2010 - 12/31/2010
USD ($)
USD ($) / shares
$c00032http://www.sec.gov/CIK0000072020duration2010-01-01T00:00:002010-12-31T00:00:00u000Standardhttp://www.xbrl.org/2003/iso4217USDiso42170u001Standardhttp://www.xbrl.org/2003/instancesharesxbrli0u002Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2true0gas_NotesToFinancialStatementsAbstractgasfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalse3false0us-gaap_InventoryDisclosureTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div style="LINE-HEIGHT: 1.5"><table style="FONT-SIZE: 10pt; LINE-HEIGHT: 1.5; FONT-FAMILY: times new roman" cellspacing="0" cellpadding="0" width="100%" align="center" border="0"><tr style="LINE-HEIGHT: 1.5" valign="top"><td style="WIDTH: 18pt; LINE-HEIGHT: 1.5"><div style="MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">5.</font></div></td><td style="LINE-HEIGHT: 1.5"><div style="LINE-HEIGHT: 1.5" align="left"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">GAS IN STORAGE</font></div></td></tr></table></div><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"><br /></div><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Gas in storage at December 31 included natural gas inventory of the following subsidiaries (in millions):</font></div><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"><br /></div><div style="LINE-HEIGHT: 1.5" align="center"><table style="FONT-SIZE: 10pt; LINE-HEIGHT: 1.5; FONT-FAMILY: times new roman" cellspacing="0" cellpadding="0" width="100%"><tr style="LINE-HEIGHT: 1.5"><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5" valign="bottom" width="32%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">  </font></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 2px solid" valign="bottom" width="7%" colspan="2"><div style="LINE-HEIGHT: 1.5" align="center"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">2010</font></div></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 2px solid" valign="bottom" width="7%" colspan="2"><div style="LINE-HEIGHT: 1.5" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">2009</font></div></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td></tr><tr><td style="LINE-HEIGHT: 1.5" valign="bottom" width="32%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">  </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="7%" colspan="2"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="7%" colspan="2"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td></tr><tr bgcolor="#e2eef5"><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="32%"><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">Nicor Gas</font></div></td><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="1%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: right" valign="bottom" width="6%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">119.2</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: right" valign="bottom" width="6%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">104.7</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td></tr><tr bgcolor="white"><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5" valign="bottom" align="left" width="32%"><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">Nicor Enerchange</font></div></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5" valign="bottom" align="left" width="1%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 2px solid; TEXT-ALIGN: left" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 2px solid; TEXT-ALIGN: right" valign="bottom" width="6%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"><font style="MARGIN-LEFT: 8.8pt"></font>44.7</font></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5" valign="bottom" align="left" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 2px solid; TEXT-ALIGN: left" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 2px solid; TEXT-ALIGN: right" valign="bottom" width="6%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"><font style="MARGIN-LEFT: 8.8pt"></font>32.5</font></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td></tr><tr bgcolor="#e2eef5"><td style="PADDING-BOTTOM: 4px; LINE-HEIGHT: 1.5" valign="bottom" width="32%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">  </font></td><td style="PADDING-BOTTOM: 4px; LINE-HEIGHT: 1.5" valign="bottom" align="left" width="1%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 4px double; TEXT-ALIGN: left" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 4px double; TEXT-ALIGN: right" valign="bottom" width="6%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">163.9</font></td><td style="PADDING-BOTTOM: 4px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="PADDING-BOTTOM: 4px; LINE-HEIGHT: 1.5" valign="bottom" align="left" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 4px double; TEXT-ALIGN: left" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 4px double; TEXT-ALIGN: right" valign="bottom" width="6%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">137.2</font></td><td style="PADDING-BOTTOM: 4px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td></tr></table></div><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"><br /></div><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Nicor Gas’ inventory is carried at cost on a LIFO basis.  Nicor Enerchange’s inventory is carried at the lower of weighted-average cost or market.</font></div><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"><br /></div><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Based on the average cost of gas purchased in December 2010 and 2009, the estimated replacement cost of Nicor Gas’ inventory at December 31, 2010 and 2009 exceeded the LIFO cost by $226.8 million and $288.5 million, respectively.</font></div><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"><br /></div><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">During 2009, Nicor Gas liquidated 8.8 Bcf of its LIFO-based inventory at an average cost per Mcf of $7.83.  For gas purchased in 2009, the company’s average cost per Mcf was $3.89 lower than the average LIFO liquidation rate.  Applying LIFO cost in valuing the liquidation, as opposed to using the average gas purchase cost, had the effect of increasing the cost of gas in 2009 by $34.3 million.</font></div><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"><br /></div><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">There was no liquidation of LIFO layers during 2010 or 2008.</font></div><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"><br /></div><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Since the cost of gas, including inventory costs, is charged to customers without markup, subject to ICC review, the LIFO liquidation in 2009 had no impact on net income.</font></div><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"><br /></div><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Nicor Enerchange recorded charges of $7.4 million, $2.8 million and $8.3 million in 2010, 2009 and 2008, respectively, resulting from lower of cost or market valuations.</font></div>5.GAS IN STORAGEGas in storage at December 31 included natural gas inventory of the following subsidiaries (in millions): falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis element represents the complete disclosure related to inventory. This may include, but is not limited to, the basis of stating inventory, the method of determining inventory cost, the major classes of inventory, and the nature of the cost elements included in inventory. If inventory is stated above cost, accrued net losses on firm purchase commitments for inventory and losses resulting from valuing inventory at the lower-of-cost-or-market may also be included. For LIFO inventory, may disclose the amount and basis for determining the excess of replacement or current cost over stated LIFO value and the effects of a LIFO quantities liquidation that impacts net income.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 3
-Section A
-Paragraph 9
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 6
-Subparagraph a, b, c
-Article 5
falsefalse12GAS IN STORAGEUnKnownUnKnownUnKnownUnKnownfalsetrue