2.2.0.25falsefalse006040 - Disclosure - INVESTMENTStruefalsefalse1falsefalseUSDfalsefalse1/1/2011 - 3/31/2011
USD ($)
USD ($) / shares
$c00012http://www.sec.gov/CIK0000072020duration2011-01-01T00:00:002011-03-31T00:00:00u000Standardhttp://www.xbrl.org/2003/iso4217USDiso42170u001Standardhttp://www.xbrl.org/2003/instancesharesxbrli0u002Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2true0gas_NotesToFinancialStatementsAbstractgasfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse| 1falsefalsefalse00falsefalsefalsefalsefalse | Otherxbrli:stringItemTypestringNo definition available.falsefalse
3false0us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse| 1falsefalsefalse00<div><table style="FONT-SIZE: 10pt; 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"><div style="MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">4.</font></div></td><td><div align="left"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">INVESTMENTS</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">The company’s investments in debt and equity securities are as follows (in millions):</font></div><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"><br /></div><div align="center"><table style="FONT-SIZE: 10pt; FONT-FAMILY: times new roman" cellspacing="0" cellpadding="0" width="100%"><tr><td valign="bottom" width="25%"><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-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="7%" colspan="2"><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">March 31</font></div></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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" width="2%"><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"><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">December 31</font></div></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="2%"><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"><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">March 31</font></div></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><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5" valign="bottom" width="25%"><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="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">2011</font></div></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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="2%"><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="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; 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="2%"><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="2%"><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="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; 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-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td></tr><tr><td style="LINE-HEIGHT: 1.5" valign="bottom" width="25%"><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="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="2%"><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="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="2%"><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="white"><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="25%"><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">Money market funds</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">69.1</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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="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" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: right" valign="bottom" width="6%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">82.9</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</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">111.8</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="25%"><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">Corporate bonds</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"><font style="MARGIN-LEFT: 15.85pt"></font>6.6</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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="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" 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"><font style="MARGIN-LEFT: 28.4pt"></font>6.8</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="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" 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"><font style="MARGIN-LEFT: 35.05pt"></font>.8</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="25%"><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">Other investments</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: 15.85pt"></font>9.1</font></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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="2%"><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: 28.4pt"></font>8.5</font></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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" align="left" width="2%"><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: 28.4pt"></font>5.0</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="25%"><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">$</font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 4px double; TEXT-ALIGN: right" valign="bottom" width="6%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">84.8</font></td><td style="PADDING-BOTTOM: 4px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="PADDING-BOTTOM: 4px; LINE-HEIGHT: 1.5" valign="bottom" align="left" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 4px double; TEXT-ALIGN: left" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</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">98.2</font></td><td style="PADDING-BOTTOM: 4px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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="2%"><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">117.6</font></td><td style="PADDING-BOTTOM: 4px; 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">Investments in debt and equity securities are classified on the Condensed Consolidated Balance Sheets as follows (in millions):</font></div><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"><br /></div><div align="center"><table style="FONT-SIZE: 10pt; FONT-FAMILY: times new roman" cellspacing="0" cellpadding="0" width="100%"><tr><td valign="bottom" width="25%"><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-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="7%" colspan="2"><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">March 31</font></div></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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" width="2%"><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"><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">December 31</font></div></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="2%"><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"><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">March 31</font></div></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><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5" valign="bottom" width="25%"><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="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">2011</font></div></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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="2%"><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="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; 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="2%"><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="2%"><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="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; 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-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td></tr><tr><td style="LINE-HEIGHT: 1.5" valign="bottom" width="25%"><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="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="2%"><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="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="2%"><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><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="25%"><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">Cash equivalents</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">8.8</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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="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" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: right" valign="bottom" width="6%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">12.6</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</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">41.2</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="25%"><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">Short-term investments</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"><font style="MARGIN-LEFT: 9.2pt"></font>61.1</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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="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" 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"><font style="MARGIN-LEFT: 21.75pt"></font>70.6</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="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" 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"><font style="MARGIN-LEFT: 21.75pt"></font>70.9</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="25%"><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">Long-term investments</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: 9.2pt"></font>14.9</font></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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="2%"><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: 21.75pt"></font>15.0</font></td><td style="PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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" align="left" width="2%"><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: 28.4pt"></font>5.5</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="25%"><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">$</font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 4px double; TEXT-ALIGN: right" valign="bottom" width="6%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">84.8</font></td><td style="PADDING-BOTTOM: 4px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="PADDING-BOTTOM: 4px; LINE-HEIGHT: 1.5" valign="bottom" align="left" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 4px double; TEXT-ALIGN: left" valign="bottom" width="1%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</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">98.2</font></td><td style="PADDING-BOTTOM: 4px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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="2%"><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">117.6</font></td><td style="PADDING-BOTTOM: 4px; 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">Investments categorized as trading (including money market funds) totaled $71.6 million, $85.0 million and $113.8 million at March 31, 2011, December 31, 2010 and March 31, 2010, respectively.  Corporate bonds and certain other investments are categorized as held-to-maturity.  The contractual maturities of the held-to-maturity investments at March 31, 2011 are as follows (in millions):</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="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Years to maturity</font></div><div align="center"><table style="FONT-SIZE: 10pt; FONT-FAMILY: times new roman" cellspacing="0" cellpadding="0" width="100%"><tr><td style="BORDER-TOP: black 0.5pt solid; LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 2px solid" valign="bottom" width="21%" colspan="2"><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">Less</font></div><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">than 1 year</font></div></td><td style="BORDER-TOP: black 0.5pt solid; PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="BORDER-TOP: black 0.5pt solid; PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5" valign="bottom" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="BORDER-TOP: black 0.5pt solid; LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 2px solid" valign="bottom" width="21%" colspan="2"><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">1-5</font></div><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">Years</font></div></td><td style="BORDER-TOP: black 0.5pt solid; PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="BORDER-TOP: black 0.5pt solid; PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5" valign="bottom" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="BORDER-TOP: black 0.5pt solid; LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 2px solid" valign="bottom" width="21%" colspan="2"><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">5-10</font></div><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">Years</font></div></td><td style="BORDER-TOP: black 0.5pt solid; PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="BORDER-TOP: black 0.5pt solid; PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5" valign="bottom" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="BORDER-TOP: black 0.5pt solid; LINE-HEIGHT: 1.5; BORDER-BOTTOM: black 2px solid" valign="bottom" width="21%" colspan="2"><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"> </div><div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">Total</font></div></td><td style="BORDER-TOP: black 0.5pt solid; PADDING-BOTTOM: 2px; LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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="21%" 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="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="21%" 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="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="21%" 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="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" width="21%" 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="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td></tr><tr bgcolor="#e2eef5"><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: center" valign="bottom" width="9%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: center" valign="bottom" width="12%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">.4</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="2%"><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="9%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: center" valign="bottom" width="12%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">7.3</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: right" valign="bottom" width="9%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: center" valign="bottom" width="12%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">.9</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> </font></td><td style="LINE-HEIGHT: 1.5" valign="bottom" align="left" width="2%"><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="9%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">$</font></td><td style="LINE-HEIGHT: 1.5; TEXT-ALIGN: center" valign="bottom" width="12%"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">8.6</font></td><td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="2%"><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’s investments also include certain restricted investments, including certificates of deposit and bank accounts, maintained to fulfill statutory or contractual requirements.  These investments totaled $2.2 million, $2.0 million and $3.0 million at March 31, 2011, December 31, 2010 and March 31, 2010, respectively.  In addition, at March 31, 2011 and December 31, 2010, the company held a $2.4 million investment in a port facility development venture carried at cost.</font></div><div style="DISPLAY: block; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.5"> </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 were no gains or losses included in earnings resulting from the sale of investments for the periods ended March 31, 2011 and 2010.</font></div>4.INVESTMENTSThe company’s investments in debt and equity securities are as follows (in millions):   March 31  Decemberfalsefalsefalsefalsefalse | Otherus-types:textBlockItemTypestringThis item represents the entire disclosure related to Investments in Certain Debt and Equity Securities (and certain other trading assets) which include all debt and equity securities (other than those equity securities accounted for under the equity or cost methods of accounting) with readily determinable fair values. Other trading assets include assets that are carried on the balance sheet at fair value and held for trading purposes. A debt security represents a creditor relationship with an enterprise that is in the form of a security. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities (and other trading assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 3, 19, 20, 21, 22, 137
falsefalse
12INVESTMENTSUnKnownUnKnownUnKnownUnKnownfalsetrue