v2.4.0.6

Income Taxes (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2012
Income Tax [Line Items] |
Schedule of Components of Income Tax Expense (Benefit) | The components of “Income tax expense (benefit)” in the Consolidated Statements of Income were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Current tax expense (benefit): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal |  | ($29.3 | ) |  |  | $58.6 |  |  |  | $7.1 |  |  |  | ($7.7 | ) |  |  | $54.5 |  |  |  | ($22.4 | ) |  |  | $7.2 |  |  |  | ($4.3 | ) |  |  | $26.8 |
State | 11.6 |  |  | 15.7 |  |  | 10.6 |  |  | 9.1 |  |  | 20.0 |  |  | (7.6 | ) |  | (0.9 | ) |  | (7.1 | ) |  | 14.7 |
IPL’s electric tax benefit rider | (48.3 | ) |  | (35.9 | ) |  | — |  |  | (48.3 | ) |  | (35.9 | ) |  | — |  |  | — |  |  | — |  |  | — |
Deferred tax expense (benefit): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal | 157.8 |  |  | 99.0 |  |  | 165.5 |  |  | 37.4 |  |  | (11.6 | ) |  | 100.9 |  |  | 81.1 |  |  | 111.3 |  |  | 63.3 |
State | 23.9 |  |  | (16.8 | ) |  | 4.9 |  |  | 3.2 |  |  | (16.4 | ) |  | (2.8 | ) |  | 20.3 |  |  | 19.0 |  |  | 6.6 |
Production tax credits | (24.8 | ) |  | (27.1 | ) |  | (11.2 | ) |  | (12.5 | ) |  | (12.3 | ) |  | (7.7 | ) |  | (12.3 | ) |  | (14.8 | ) |  | (3.5 | )
Investment tax credits | (1.7 | ) |  | (1.8 | ) |  | (1.8 | ) |  | (0.6 | ) |  | (0.6 | ) |  | (0.6 | ) |  | (1.1 | ) |  | (1.2 | ) |  | (1.2 | )
Provision recorded as a change in uncertain tax positions: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | 8.0 |  |  | 16.3 |  |  | (84.0 | ) |  | 8.1 |  |  | 16.6 |  |  | (41.1 | ) |  | (0.1 | ) |  | (0.3 | ) |  | (41.7 | )
Deferred | (7.6 | ) |  | (38.3 | ) |  | 59.6 |  |  | (8.2 | ) |  | (17.6 | ) |  | 26.2 |  |  | 0.6 |  |  | (20.7 | ) |  | 33.3 |
Provision recorded as a change in accrued interest | (0.2 | ) |  | (0.5 | ) |  | (3.0 | ) |  | (0.3 | ) |  | (0.3 | ) |  | (2.6 | ) |  | (0.2 | ) |  | — |  |  | — |
|  | $89.4 |  |  |  | $69.2 |  |  |  | $147.7 |  |  |  | ($19.8 | ) |  |  | ($3.6 | ) |  |  | $42.3 |  |  |  | $94.6 |  |  |  | $81.9 |  |  |  | $98.3 |
Schedule Of Effective Income Tax Rates | The overall income tax rates shown in the following table were computed by dividing income tax expense (benefit) by income from continuing operations before income taxes.
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Statutory federal income tax rate | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | %
State income taxes, net of federal benefits | 5.7 |  |  | 4.6 |  |  | 4.8 |  |  | 5.8 |  |  | 4.3 |  |  | 4.1 |  |  | 5.5 |  |  | 5.0 |  |  | 5.1 |
State apportionment change due to announced sale of RMT | 3.5 |  |  | — |  |  | — |  |  | 6.2 |  |  | — |  |  | — |  |  | 2.7 |  |  | — |  |  | — |
IPL’s electric tax benefit rider | (11.2 | ) |  | (8.8 | ) |  | — |  |  | (37.0 | ) |  | (26.5 | ) |  | — |  |  | — |  |  | — |  |  | — |
Production tax credits | (5.8 | ) |  | (6.6 | ) |  | (2.4 | ) |  | (9.6 | ) |  | (9.1 | ) |  | (4.1 | ) |  | (4.7 | ) |  | (6.0 | ) |  | (1.4 | )
Effect of rate-making on property-related differences | (5.0 | ) |  | (2.0 | ) |  | (4.2 | ) |  | (14.2 | ) |  | (5.3 | ) |  | (8.9 | ) |  | (1.1 | ) |  | (0.5 | ) |  | (1.1 | )
Adjustment of prior period taxes | — |  |  | 0.2 |  |  | 0.3 |  |  | 0.2 |  |  | 1.7 |  |  | (1.8 | ) |  | (0.3 | ) |  | — |  |  | 2.0 |
Wisconsin tax legislation | — |  |  | (4.6 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Federal Health Care Legislation | — |  |  | — |  |  | 1.6 |  |  | — |  |  | — |  |  | 2.0 |  |  | — |  |  | — |  |  | 1.2 |
Other items, net | (1.4 | ) |  | (0.9 | ) |  | (2.8 | ) |  | (1.6 | ) |  | (2.8 | ) |  | (3.5 | ) |  | (0.8 | ) |  | (0.1 | ) |  | (1.6 | )
Overall income tax rate | 20.8 | % |  | 16.9 | % |  | 32.3 | % |  | (15.2 | %) |  | (2.7 | %) |  | 22.8 | % |  | 36.3 | % |  | 33.4 | % |  | 39.2 | %
Production Tax Credits (Net Of State Tax Impacts) | Production tax credits (net of state tax impacts) resulting from these wind projects were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Whispering Willow - East (IPL) |  | $12.5 |  |  |  | $12.3 |  |  |  | $7.7 |  |  |  | $12.5 |  |  |  | $12.3 |  |  |  | $7.7 |  |  |  | $— |  |  |  | $— |  |  |  | $— |
Bent Tree - Phase I (WPL) (a) | 9.3 |  |  | 9.3 |  |  | 1.2 |  |  | — |  |  | — |  |  | — |  |  | 9.3 |  |  | 9.3 |  |  | 1.2 |
Cedar Ridge (WPL) | 4.0 |  |  | 4.5 |  |  | 3.3 |  |  | — |  |  | — |  |  | — |  |  | 4.0 |  |  | 4.5 |  |  | 3.3 |
| 25.8 |  |  | 26.1 |  |  | 12.2 |  |  | 12.5 |  |  | 12.3 |  |  | 7.7 |  |  | 13.3 |  |  | 13.8 |  |  | 4.5 |
Deferral (a) | (1.0 | ) |  | 1.0 |  |  | (1.0 | ) |  | — |  |  | — |  |  | — |  |  | (1.0 | ) |  | 1.0 |  |  | (1.0 | )
|  | $24.8 |  |  |  | $27.1 |  |  |  | $11.2 |  |  |  | $12.5 |  |  |  | $12.3 |  |  |  | $7.7 |  |  |  | $12.3 |  |  |  | $14.8 |  |  |  | $3.5 |
(a) | In 2010 and 2012, WPL deferred the retail portion of the production tax credits generated in 2010 from its Bent Tree - Phase I wind project pursuant to orders issued by the PSCW in December 2009 and July 2012, respectively. As a result of a regulatory assessment completed in 2011, the retail portion of the production tax credit deferral recorded in 2010 was reversed.
Schedule of Deferred Tax Assets and Liabilities | The deferred income tax (assets) and liabilities included on Alliant Energy’s Consolidated Balance Sheets at December 31 arise from the following temporary differences (in millions):
| 2012 |  | 2011
| Deferred | Deferred Tax |  |  | Deferred | Deferred Tax |
Alliant Energy | Tax Assets | Liabilities | Net |  | Tax Assets | Liabilities | Net
Property |  | $— |  |  | $2,143.8 |  |  | $2,143.8 |  |  |  | $— |  |  | $1,926.4 |  |  | $1,926.4 |
Investment in ATC | — |  | 104.3 |  | 104.3 |  |  | — |  | 93.8 |  | 93.8 |
Deferred portion of tax gain on IPL’s electric transmission assets sale | — |  | 50.7 |  | 50.7 |  |  | — |  | 75.5 |  | 75.5 |
Net operating losses carryforward - state | (46.8 | ) | — |  | (46.8 | ) |  | (39.9 | ) | — |  | (39.9 | )
Federal credit carryforward | (133.8 | ) | — |  | (133.8 | ) |  | (107.4 | ) | — |  | (107.4 | )
Regulatory liability - IPL’s tax benefit rider | (144.6 | ) | — |  | (144.6 | ) |  | (140.6 | ) | — |  | (140.6 | )
Net operating losses carryforward - federal | (306.0 | ) | — |  | (306.0 | ) |  | (336.1 | ) | — |  | (336.1 | )
Other | (113.7 | ) | 208.2 |  | 94.5 |  |  | (128.2 | ) | 224.7 |  | 96.5 |
Subtotal | (744.9 | ) | 2,507.0 |  | 1,762.1 |  |  | (752.2 | ) | 2,320.4 |  | 1,568.2 |
Valuation allowances | 1.9 |  | — |  | 1.9 |  |  | 1.2 |  | — |  | 1.2 |
|  | ($743.0 | ) |  | $2,507.0 |  |  | $1,764.0 |  |  |  | ($751.0 | ) |  | $2,320.4 |  |  | $1,569.4 |
| 2012 |  | 2011
Other current assets |  | ($170.2 | ) |  |  | ($22.8 | )
Deferred income taxes | 1,934.2 |  |  | 1,592.2 |
Total deferred tax liabilities |  | $1,764.0 |  |  |  | $1,569.4 |
Summary Of Tax Credit Carryforwards | At December 31, 2012, tax carryforwards and associated deferred tax assets and expiration dates were estimated as follows (in millions):
Alliant Energy | Tax Carryforwards |  | Deferred Tax Assets |  | Earliest Expiration Date
Federal net operating losses |  | $892 |  |  |  | $306 |  |  | 2029
State net operating losses | 871 |  |  | 47 |  |  | 2014
Federal tax credits | 136 |  |  | 134 |  |  | 2022
|  |  |  | $487 |  |  |
IPL | Tax Carryforwards |  | Deferred Tax Assets |  | Earliest Expiration Date
Federal net operating losses |  | $382 |  |  |  | $131 |  |  | 2029
State net operating losses | 254 |  |  | 15 |  |  | 2018
Federal tax credits | 38 |  |  | 37 |  |  | 2022
|  |  |  | $183 |  |  |
WPL | Tax Carryforwards |  | Deferred Tax Assets |  | Earliest Expiration Date
Federal net operating losses |  | $414 |  |  |  | $142 |  |  | 2029
State net operating losses | 152 |  |  | 8 |  |  | 2018
Federal tax credits | 40 |  |  | 39 |  |  | 2022
|  |  |  | $189 |  |  |
Summary of Uncertain Tax Positions | A reconciliation of the beginning and ending amounts of uncertain tax positions, excluding interest, is as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Balance, January 1 |  | $23.5 |  |  |  | $66.7 |  |  |  | $101.7 |  |  |  | $10.9 |  |  |  | $33.0 |  |  |  | $58.4 |  |  |  | $12.6 |  |  |  | $33.7 |  |  |  | $42.1 |
Additions based on tax positions related to the current year | 0.7 |  |  | 0.7 |  |  | 3.8 |  |  | — |  |  | 0.1 |  |  | 2.5 |  |  | 0.7 |  |  | 0.6 |  |  | 1.3 |
Additions for tax positions of prior years (a) | — |  |  | — |  |  | 9.1 |  |  | — |  |  | — |  |  | 3.8 |  |  | — |  |  | — |  |  | 5.2 |
Reductions for tax positions of prior years (b) | (23.5 | ) |  | (43.9 | ) |  | (31.8 | ) |  | (10.9 | ) |  | (22.2 | ) |  | (22.7 | ) |  | (12.6 | ) |  | (21.7 | ) |  | (8.0 | )
Settlements with taxing authorities | — |  |  | — |  |  | (16.1 | ) |  | — |  |  | — |  |  | (9.0 | ) |  | — |  |  | — |  |  | (6.9 | )
Balance, December 31 (c) |  | $0.7 |  |  |  | $23.5 |  |  |  | $66.7 |  |  |  | $— |  |  |  | $10.9 |  |  |  | $33.0 |  |  |  | $0.7 |  |  |  | $12.6 |  |  |  | $33.7 |
(a) | The additions for tax positions of prior years were related to positions taken by Alliant Energy, IPL and WPL on their federal and state tax returns related to the capitalization and dispositions of property.
(b) | In 2012, the reductions for tax positions of prior years were due to the finalization of Alliant Energy’s federal income tax return audits for calendar years 2005 through 2009. In 2011, the reductions for tax positions of prior years were related to guidance published by the IRS clarifying the treatment of repair expenditures for electric distribution property. In 2010, the reductions of tax positions of prior years were primarily related to deductions taken by Alliant Energy, IPL and WPL on their federal and state tax returns that were settled under audit for amounts less than the reductions of tax positions recorded.
(c) | At December 31, 2012 and 2011, $0 and $10 million, respectively, of uncertain tax positions balances for both Alliant Energy and IPL included amounts recorded in regulatory liability accounts.
At December 31, 2012, 2011 and 2010, there were no penalties accrued related to uncertain tax positions. Additional information regarding uncertain tax positions at December 31 is as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Tax positions favorably impacting future effective tax rates for continuing operations |  | $0.7 |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $0.7 |  |  |  | $— |  |  |  | $— |
Interest accrued | — |  |  | 0.4 |  |  | 0.7 |  |  | — |  |  | 0.4 |  |  | 0.7 |  |  | — |  |  | — |  |  | — |
Schedule Of Open Tax Years | Open tax years - Tax years that remain subject to the statute of limitations are as follows:
Major Jurisdiction |  | Alliant Energy |  | IPL |  | WPL
Consolidated federal income tax returns (a) |  | 2005 | - | 2011 |  | 2005 | - | 2011 |  | 2005 | - | 2011
Consolidated Iowa income tax returns (b) |  | 2005 | - | 2011 |  | 2005 | - | 2011 |  | 2005 | - | 2011
Wisconsin income tax returns |  | 2005 | - | 2008 |  | N/A |  | 2005 | - | 2008
Wisconsin combined tax returns |  | 2009 | - | 2011 |  | 2009 | - | 2011 |  | 2009 | - | 2011
(a) | 2005 through 2010 are effectively settled. The statute of limitations for 2005 through 2008 has been extended to June 30, 2013. The statute of limitations for 2009 through 2011 expires three years from the extended due date of the federal tax return.
(b) | 2005 through 2008 are open for federal audit adjustments only.
IPL [Member] |
Income Tax [Line Items] |
Schedule of Components of Income Tax Expense (Benefit) | The components of “Income tax expense (benefit)” in the Consolidated Statements of Income were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Current tax expense (benefit): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal |  | ($29.3 | ) |  |  | $58.6 |  |  |  | $7.1 |  |  |  | ($7.7 | ) |  |  | $54.5 |  |  |  | ($22.4 | ) |  |  | $7.2 |  |  |  | ($4.3 | ) |  |  | $26.8 |
State | 11.6 |  |  | 15.7 |  |  | 10.6 |  |  | 9.1 |  |  | 20.0 |  |  | (7.6 | ) |  | (0.9 | ) |  | (7.1 | ) |  | 14.7 |
IPL’s electric tax benefit rider | (48.3 | ) |  | (35.9 | ) |  | — |  |  | (48.3 | ) |  | (35.9 | ) |  | — |  |  | — |  |  | — |  |  | — |
Deferred tax expense (benefit): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal | 157.8 |  |  | 99.0 |  |  | 165.5 |  |  | 37.4 |  |  | (11.6 | ) |  | 100.9 |  |  | 81.1 |  |  | 111.3 |  |  | 63.3 |
State | 23.9 |  |  | (16.8 | ) |  | 4.9 |  |  | 3.2 |  |  | (16.4 | ) |  | (2.8 | ) |  | 20.3 |  |  | 19.0 |  |  | 6.6 |
Production tax credits | (24.8 | ) |  | (27.1 | ) |  | (11.2 | ) |  | (12.5 | ) |  | (12.3 | ) |  | (7.7 | ) |  | (12.3 | ) |  | (14.8 | ) |  | (3.5 | )
Investment tax credits | (1.7 | ) |  | (1.8 | ) |  | (1.8 | ) |  | (0.6 | ) |  | (0.6 | ) |  | (0.6 | ) |  | (1.1 | ) |  | (1.2 | ) |  | (1.2 | )
Provision recorded as a change in uncertain tax positions: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | 8.0 |  |  | 16.3 |  |  | (84.0 | ) |  | 8.1 |  |  | 16.6 |  |  | (41.1 | ) |  | (0.1 | ) |  | (0.3 | ) |  | (41.7 | )
Deferred | (7.6 | ) |  | (38.3 | ) |  | 59.6 |  |  | (8.2 | ) |  | (17.6 | ) |  | 26.2 |  |  | 0.6 |  |  | (20.7 | ) |  | 33.3 |
Provision recorded as a change in accrued interest | (0.2 | ) |  | (0.5 | ) |  | (3.0 | ) |  | (0.3 | ) |  | (0.3 | ) |  | (2.6 | ) |  | (0.2 | ) |  | — |  |  | — |
|  | $89.4 |  |  |  | $69.2 |  |  |  | $147.7 |  |  |  | ($19.8 | ) |  |  | ($3.6 | ) |  |  | $42.3 |  |  |  | $94.6 |  |  |  | $81.9 |  |  |  | $98.3 |
Schedule Of Effective Income Tax Rates | The overall income tax rates shown in the following table were computed by dividing income tax expense (benefit) by income from continuing operations before income taxes.
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Statutory federal income tax rate | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | %
State income taxes, net of federal benefits | 5.7 |  |  | 4.6 |  |  | 4.8 |  |  | 5.8 |  |  | 4.3 |  |  | 4.1 |  |  | 5.5 |  |  | 5.0 |  |  | 5.1 |
State apportionment change due to announced sale of RMT | 3.5 |  |  | — |  |  | — |  |  | 6.2 |  |  | — |  |  | — |  |  | 2.7 |  |  | — |  |  | — |
IPL’s electric tax benefit rider | (11.2 | ) |  | (8.8 | ) |  | — |  |  | (37.0 | ) |  | (26.5 | ) |  | — |  |  | — |  |  | — |  |  | — |
Production tax credits | (5.8 | ) |  | (6.6 | ) |  | (2.4 | ) |  | (9.6 | ) |  | (9.1 | ) |  | (4.1 | ) |  | (4.7 | ) |  | (6.0 | ) |  | (1.4 | )
Effect of rate-making on property-related differences | (5.0 | ) |  | (2.0 | ) |  | (4.2 | ) |  | (14.2 | ) |  | (5.3 | ) |  | (8.9 | ) |  | (1.1 | ) |  | (0.5 | ) |  | (1.1 | )
Adjustment of prior period taxes | — |  |  | 0.2 |  |  | 0.3 |  |  | 0.2 |  |  | 1.7 |  |  | (1.8 | ) |  | (0.3 | ) |  | — |  |  | 2.0 |
Wisconsin tax legislation | — |  |  | (4.6 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Federal Health Care Legislation | — |  |  | — |  |  | 1.6 |  |  | — |  |  | — |  |  | 2.0 |  |  | — |  |  | — |  |  | 1.2 |
Other items, net | (1.4 | ) |  | (0.9 | ) |  | (2.8 | ) |  | (1.6 | ) |  | (2.8 | ) |  | (3.5 | ) |  | (0.8 | ) |  | (0.1 | ) |  | (1.6 | )
Overall income tax rate | 20.8 | % |  | 16.9 | % |  | 32.3 | % |  | (15.2 | %) |  | (2.7 | %) |  | 22.8 | % |  | 36.3 | % |  | 33.4 | % |  | 39.2 | %
Production Tax Credits (Net Of State Tax Impacts) | Production tax credits (net of state tax impacts) resulting from these wind projects were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Whispering Willow - East (IPL) |  | $12.5 |  |  |  | $12.3 |  |  |  | $7.7 |  |  |  | $12.5 |  |  |  | $12.3 |  |  |  | $7.7 |  |  |  | $— |  |  |  | $— |  |  |  | $— |
Bent Tree - Phase I (WPL) (a) | 9.3 |  |  | 9.3 |  |  | 1.2 |  |  | — |  |  | — |  |  | — |  |  | 9.3 |  |  | 9.3 |  |  | 1.2 |
Cedar Ridge (WPL) | 4.0 |  |  | 4.5 |  |  | 3.3 |  |  | — |  |  | — |  |  | — |  |  | 4.0 |  |  | 4.5 |  |  | 3.3 |
| 25.8 |  |  | 26.1 |  |  | 12.2 |  |  | 12.5 |  |  | 12.3 |  |  | 7.7 |  |  | 13.3 |  |  | 13.8 |  |  | 4.5 |
Deferral (a) | (1.0 | ) |  | 1.0 |  |  | (1.0 | ) |  | — |  |  | — |  |  | — |  |  | (1.0 | ) |  | 1.0 |  |  | (1.0 | )
|  | $24.8 |  |  |  | $27.1 |  |  |  | $11.2 |  |  |  | $12.5 |  |  |  | $12.3 |  |  |  | $7.7 |  |  |  | $12.3 |  |  |  | $14.8 |  |  |  | $3.5 |
(a) | In 2010 and 2012, WPL deferred the retail portion of the production tax credits generated in 2010 from its Bent Tree - Phase I wind project pursuant to orders issued by the PSCW in December 2009 and July 2012, respectively. As a result of a regulatory assessment completed in 2011, the retail portion of the production tax credit deferral recorded in 2010 was reversed.
Schedule of Deferred Tax Assets and Liabilities | The deferred income tax (assets) and liabilities included on IPL’s Consolidated Balance Sheets at December 31 arise from the following temporary differences (in millions):
| 2012 |  | 2011
| Deferred | Deferred Tax |  |  | Deferred | Deferred Tax |
IPL | Tax Assets | Liabilities | Net |  | Tax Assets | Liabilities | Net
Property |  | $— |  |  | $1,243.9 |  |  | $1,243.9 |  |  |  | $— |  |  | $1,134.1 |  |  | $1,134.1 |
Pension and other postretirement benefits obligations | — |  | 64.9 |  | 64.9 |  |  | — |  | 67.6 |  | 67.6 |
Deferred portion of tax gain on electric transmission assets sale | — |  | 50.7 |  | 50.7 |  |  | — |  | 75.5 |  | 75.5 |
Federal credit carryforward | (37.4 | ) | — |  | (37.4 | ) |  | (25.0 | ) | — |  | (25.0 | )
Net operating losses carryforward - federal | (131.0 | ) | — |  | (131.0 | ) |  | (154.4 | ) | — |  | (154.4 | )
Regulatory liability - tax benefit rider | (144.6 | ) | — |  | (144.6 | ) |  | (140.6 | ) | — |  | (140.6 | )
Other | (70.4 | ) | 31.9 |  | (38.5 | ) |  | (76.5 | ) | 42.7 |  | (33.8 | )
|  | ($383.4 | ) |  | $1,391.4 |  |  | $1,008.0 |  |  |  | ($396.5 | ) |  | $1,319.9 |  |  | $923.4 |
| 2012 |  | 2011
Other current assets |  | ($79.3 | ) |  |  | ($13.5 | )
Deferred income taxes | 1,087.3 |  |  | 936.9 |
Total deferred tax liabilities |  | $1,008.0 |  |  |  | $923.4 |
Summary Of Tax Credit Carryforwards | At December 31, 2012, tax carryforwards and associated deferred tax assets and expiration dates were estimated as follows (in millions):
Alliant Energy | Tax Carryforwards |  | Deferred Tax Assets |  | Earliest Expiration Date
Federal net operating losses |  | $892 |  |  |  | $306 |  |  | 2029
State net operating losses | 871 |  |  | 47 |  |  | 2014
Federal tax credits | 136 |  |  | 134 |  |  | 2022
|  |  |  | $487 |  |  |
IPL | Tax Carryforwards |  | Deferred Tax Assets |  | Earliest Expiration Date
Federal net operating losses |  | $382 |  |  |  | $131 |  |  | 2029
State net operating losses | 254 |  |  | 15 |  |  | 2018
Federal tax credits | 38 |  |  | 37 |  |  | 2022
|  |  |  | $183 |  |  |
WPL | Tax Carryforwards |  | Deferred Tax Assets |  | Earliest Expiration Date
Federal net operating losses |  | $414 |  |  |  | $142 |  |  | 2029
State net operating losses | 152 |  |  | 8 |  |  | 2018
Federal tax credits | 40 |  |  | 39 |  |  | 2022
|  |  |  | $189 |  |  |
Summary of Uncertain Tax Positions | A reconciliation of the beginning and ending amounts of uncertain tax positions, excluding interest, is as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Balance, January 1 |  | $23.5 |  |  |  | $66.7 |  |  |  | $101.7 |  |  |  | $10.9 |  |  |  | $33.0 |  |  |  | $58.4 |  |  |  | $12.6 |  |  |  | $33.7 |  |  |  | $42.1 |
Additions based on tax positions related to the current year | 0.7 |  |  | 0.7 |  |  | 3.8 |  |  | — |  |  | 0.1 |  |  | 2.5 |  |  | 0.7 |  |  | 0.6 |  |  | 1.3 |
Additions for tax positions of prior years (a) | — |  |  | — |  |  | 9.1 |  |  | — |  |  | — |  |  | 3.8 |  |  | — |  |  | — |  |  | 5.2 |
Reductions for tax positions of prior years (b) | (23.5 | ) |  | (43.9 | ) |  | (31.8 | ) |  | (10.9 | ) |  | (22.2 | ) |  | (22.7 | ) |  | (12.6 | ) |  | (21.7 | ) |  | (8.0 | )
Settlements with taxing authorities | — |  |  | — |  |  | (16.1 | ) |  | — |  |  | — |  |  | (9.0 | ) |  | — |  |  | — |  |  | (6.9 | )
Balance, December 31 (c) |  | $0.7 |  |  |  | $23.5 |  |  |  | $66.7 |  |  |  | $— |  |  |  | $10.9 |  |  |  | $33.0 |  |  |  | $0.7 |  |  |  | $12.6 |  |  |  | $33.7 |
(a) | The additions for tax positions of prior years were related to positions taken by Alliant Energy, IPL and WPL on their federal and state tax returns related to the capitalization and dispositions of property.
(b) | In 2012, the reductions for tax positions of prior years were due to the finalization of Alliant Energy’s federal income tax return audits for calendar years 2005 through 2009. In 2011, the reductions for tax positions of prior years were related to guidance published by the IRS clarifying the treatment of repair expenditures for electric distribution property. In 2010, the reductions of tax positions of prior years were primarily related to deductions taken by Alliant Energy, IPL and WPL on their federal and state tax returns that were settled under audit for amounts less than the reductions of tax positions recorded.
(c) | At December 31, 2012 and 2011, $0 and $10 million, respectively, of uncertain tax positions balances for both Alliant Energy and IPL included amounts recorded in regulatory liability accounts.
At December 31, 2012, 2011 and 2010, there were no penalties accrued related to uncertain tax positions. Additional information regarding uncertain tax positions at December 31 is as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Tax positions favorably impacting future effective tax rates for continuing operations |  | $0.7 |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $0.7 |  |  |  | $— |  |  |  | $— |
Interest accrued | — |  |  | 0.4 |  |  | 0.7 |  |  | — |  |  | 0.4 |  |  | 0.7 |  |  | — |  |  | — |  |  | — |
Schedule Of Open Tax Years | Open tax years - Tax years that remain subject to the statute of limitations are as follows:
Major Jurisdiction |  | Alliant Energy |  | IPL |  | WPL
Consolidated federal income tax returns (a) |  | 2005 | - | 2011 |  | 2005 | - | 2011 |  | 2005 | - | 2011
Consolidated Iowa income tax returns (b) |  | 2005 | - | 2011 |  | 2005 | - | 2011 |  | 2005 | - | 2011
Wisconsin income tax returns |  | 2005 | - | 2008 |  | N/A |  | 2005 | - | 2008
Wisconsin combined tax returns |  | 2009 | - | 2011 |  | 2009 | - | 2011 |  | 2009 | - | 2011
(a) | 2005 through 2010 are effectively settled. The statute of limitations for 2005 through 2008 has been extended to June 30, 2013. The statute of limitations for 2009 through 2011 expires three years from the extended due date of the federal tax return.
(b) | 2005 through 2008 are open for federal audit adjustments only.
WPL [Member] |
Income Tax [Line Items] |
Schedule of Components of Income Tax Expense (Benefit) | The components of “Income tax expense (benefit)” in the Consolidated Statements of Income were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Current tax expense (benefit): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal |  | ($29.3 | ) |  |  | $58.6 |  |  |  | $7.1 |  |  |  | ($7.7 | ) |  |  | $54.5 |  |  |  | ($22.4 | ) |  |  | $7.2 |  |  |  | ($4.3 | ) |  |  | $26.8 |
State | 11.6 |  |  | 15.7 |  |  | 10.6 |  |  | 9.1 |  |  | 20.0 |  |  | (7.6 | ) |  | (0.9 | ) |  | (7.1 | ) |  | 14.7 |
IPL’s electric tax benefit rider | (48.3 | ) |  | (35.9 | ) |  | — |  |  | (48.3 | ) |  | (35.9 | ) |  | — |  |  | — |  |  | — |  |  | — |
Deferred tax expense (benefit): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal | 157.8 |  |  | 99.0 |  |  | 165.5 |  |  | 37.4 |  |  | (11.6 | ) |  | 100.9 |  |  | 81.1 |  |  | 111.3 |  |  | 63.3 |
State | 23.9 |  |  | (16.8 | ) |  | 4.9 |  |  | 3.2 |  |  | (16.4 | ) |  | (2.8 | ) |  | 20.3 |  |  | 19.0 |  |  | 6.6 |
Production tax credits | (24.8 | ) |  | (27.1 | ) |  | (11.2 | ) |  | (12.5 | ) |  | (12.3 | ) |  | (7.7 | ) |  | (12.3 | ) |  | (14.8 | ) |  | (3.5 | )
Investment tax credits | (1.7 | ) |  | (1.8 | ) |  | (1.8 | ) |  | (0.6 | ) |  | (0.6 | ) |  | (0.6 | ) |  | (1.1 | ) |  | (1.2 | ) |  | (1.2 | )
Provision recorded as a change in uncertain tax positions: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | 8.0 |  |  | 16.3 |  |  | (84.0 | ) |  | 8.1 |  |  | 16.6 |  |  | (41.1 | ) |  | (0.1 | ) |  | (0.3 | ) |  | (41.7 | )
Deferred | (7.6 | ) |  | (38.3 | ) |  | 59.6 |  |  | (8.2 | ) |  | (17.6 | ) |  | 26.2 |  |  | 0.6 |  |  | (20.7 | ) |  | 33.3 |
Provision recorded as a change in accrued interest | (0.2 | ) |  | (0.5 | ) |  | (3.0 | ) |  | (0.3 | ) |  | (0.3 | ) |  | (2.6 | ) |  | (0.2 | ) |  | — |  |  | — |
|  | $89.4 |  |  |  | $69.2 |  |  |  | $147.7 |  |  |  | ($19.8 | ) |  |  | ($3.6 | ) |  |  | $42.3 |  |  |  | $94.6 |  |  |  | $81.9 |  |  |  | $98.3 |
Schedule Of Effective Income Tax Rates | The overall income tax rates shown in the following table were computed by dividing income tax expense (benefit) by income from continuing operations before income taxes.
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Statutory federal income tax rate | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | %
State income taxes, net of federal benefits | 5.7 |  |  | 4.6 |  |  | 4.8 |  |  | 5.8 |  |  | 4.3 |  |  | 4.1 |  |  | 5.5 |  |  | 5.0 |  |  | 5.1 |
State apportionment change due to announced sale of RMT | 3.5 |  |  | — |  |  | — |  |  | 6.2 |  |  | — |  |  | — |  |  | 2.7 |  |  | — |  |  | — |
IPL’s electric tax benefit rider | (11.2 | ) |  | (8.8 | ) |  | — |  |  | (37.0 | ) |  | (26.5 | ) |  | — |  |  | — |  |  | — |  |  | — |
Production tax credits | (5.8 | ) |  | (6.6 | ) |  | (2.4 | ) |  | (9.6 | ) |  | (9.1 | ) |  | (4.1 | ) |  | (4.7 | ) |  | (6.0 | ) |  | (1.4 | )
Effect of rate-making on property-related differences | (5.0 | ) |  | (2.0 | ) |  | (4.2 | ) |  | (14.2 | ) |  | (5.3 | ) |  | (8.9 | ) |  | (1.1 | ) |  | (0.5 | ) |  | (1.1 | )
Adjustment of prior period taxes | — |  |  | 0.2 |  |  | 0.3 |  |  | 0.2 |  |  | 1.7 |  |  | (1.8 | ) |  | (0.3 | ) |  | — |  |  | 2.0 |
Wisconsin tax legislation | — |  |  | (4.6 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Federal Health Care Legislation | — |  |  | — |  |  | 1.6 |  |  | — |  |  | — |  |  | 2.0 |  |  | — |  |  | — |  |  | 1.2 |
Other items, net | (1.4 | ) |  | (0.9 | ) |  | (2.8 | ) |  | (1.6 | ) |  | (2.8 | ) |  | (3.5 | ) |  | (0.8 | ) |  | (0.1 | ) |  | (1.6 | )
Overall income tax rate | 20.8 | % |  | 16.9 | % |  | 32.3 | % |  | (15.2 | %) |  | (2.7 | %) |  | 22.8 | % |  | 36.3 | % |  | 33.4 | % |  | 39.2 | %
Production Tax Credits (Net Of State Tax Impacts) | Production tax credits (net of state tax impacts) resulting from these wind projects were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Whispering Willow - East (IPL) |  | $12.5 |  |  |  | $12.3 |  |  |  | $7.7 |  |  |  | $12.5 |  |  |  | $12.3 |  |  |  | $7.7 |  |  |  | $— |  |  |  | $— |  |  |  | $— |
Bent Tree - Phase I (WPL) (a) | 9.3 |  |  | 9.3 |  |  | 1.2 |  |  | — |  |  | — |  |  | — |  |  | 9.3 |  |  | 9.3 |  |  | 1.2 |
Cedar Ridge (WPL) | 4.0 |  |  | 4.5 |  |  | 3.3 |  |  | — |  |  | — |  |  | — |  |  | 4.0 |  |  | 4.5 |  |  | 3.3 |
| 25.8 |  |  | 26.1 |  |  | 12.2 |  |  | 12.5 |  |  | 12.3 |  |  | 7.7 |  |  | 13.3 |  |  | 13.8 |  |  | 4.5 |
Deferral (a) | (1.0 | ) |  | 1.0 |  |  | (1.0 | ) |  | — |  |  | — |  |  | — |  |  | (1.0 | ) |  | 1.0 |  |  | (1.0 | )
|  | $24.8 |  |  |  | $27.1 |  |  |  | $11.2 |  |  |  | $12.5 |  |  |  | $12.3 |  |  |  | $7.7 |  |  |  | $12.3 |  |  |  | $14.8 |  |  |  | $3.5 |
(a) | In 2010 and 2012, WPL deferred the retail portion of the production tax credits generated in 2010 from its Bent Tree - Phase I wind project pursuant to orders issued by the PSCW in December 2009 and July 2012, respectively. As a result of a regulatory assessment completed in 2011, the retail portion of the production tax credit deferral recorded in 2010 was reversed.
Schedule of Deferred Tax Assets and Liabilities | The deferred income tax (assets) and liabilities included on WPL’s Consolidated Balance Sheets at December 31 arise from the following temporary differences (in millions):
| 2012 |  | 2011
| Deferred | Deferred Tax |  |  | Deferred | Deferred Tax |
WPL | Tax Assets | Liabilities | Net |  | Tax Assets | Liabilities | Net
Property |  | $— |  |  | $793.3 |  |  | $793.3 |  |  |  | $— |  |  | $697.1 |  |  | $697.1 |
Investment in ATC | — |  | 104.3 |  | 104.3 |  |  | — |  | 93.8 |  | 93.8 |
Pension and other postretirement benefits obligations | — |  | 46.4 |  | 46.4 |  |  | — |  | 49.6 |  | 49.6 |
Customer advances | (9.6 | ) | — |  | (9.6 | ) |  | (11.6 | ) | — |  | (11.6 | )
Federal credit carryforward | (39.4 | ) | — |  | (39.4 | ) |  | (26.1 | ) | — |  | (26.1 | )
Net operating losses carryforward - federal | (142.2 | ) | — |  | (142.2 | ) |  | (141.1 | ) | — |  | (141.1 | )
Other | (31.6 | ) | 37.3 |  | 5.7 |  |  | (29.3 | ) | 34.1 |  | 4.8 |
|  | ($222.8 | ) |  | $981.3 |  |  | $758.5 |  |  |  | ($208.1 | ) |  | $874.6 |  |  | $666.5 |
| 2012 |  | 2011
Other current assets |  | ($85.6 | ) |  |  | ($6.0 | )
Deferred income taxes | 844.1 |  |  | 672.5 |
Total deferred tax liabilities |  | $758.5 |  |  |  | $666.5 |
Summary Of Tax Credit Carryforwards | At December 31, 2012, tax carryforwards and associated deferred tax assets and expiration dates were estimated as follows (in millions):
Alliant Energy | Tax Carryforwards |  | Deferred Tax Assets |  | Earliest Expiration Date
Federal net operating losses |  | $892 |  |  |  | $306 |  |  | 2029
State net operating losses | 871 |  |  | 47 |  |  | 2014
Federal tax credits | 136 |  |  | 134 |  |  | 2022
|  |  |  | $487 |  |  |
IPL | Tax Carryforwards |  | Deferred Tax Assets |  | Earliest Expiration Date
Federal net operating losses |  | $382 |  |  |  | $131 |  |  | 2029
State net operating losses | 254 |  |  | 15 |  |  | 2018
Federal tax credits | 38 |  |  | 37 |  |  | 2022
|  |  |  | $183 |  |  |
WPL | Tax Carryforwards |  | Deferred Tax Assets |  | Earliest Expiration Date
Federal net operating losses |  | $414 |  |  |  | $142 |  |  | 2029
State net operating losses | 152 |  |  | 8 |  |  | 2018
Federal tax credits | 40 |  |  | 39 |  |  | 2022
|  |  |  | $189 |  |  |
Summary of Uncertain Tax Positions | A reconciliation of the beginning and ending amounts of uncertain tax positions, excluding interest, is as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Balance, January 1 |  | $23.5 |  |  |  | $66.7 |  |  |  | $101.7 |  |  |  | $10.9 |  |  |  | $33.0 |  |  |  | $58.4 |  |  |  | $12.6 |  |  |  | $33.7 |  |  |  | $42.1 |
Additions based on tax positions related to the current year | 0.7 |  |  | 0.7 |  |  | 3.8 |  |  | — |  |  | 0.1 |  |  | 2.5 |  |  | 0.7 |  |  | 0.6 |  |  | 1.3 |
Additions for tax positions of prior years (a) | — |  |  | — |  |  | 9.1 |  |  | — |  |  | — |  |  | 3.8 |  |  | — |  |  | — |  |  | 5.2 |
Reductions for tax positions of prior years (b) | (23.5 | ) |  | (43.9 | ) |  | (31.8 | ) |  | (10.9 | ) |  | (22.2 | ) |  | (22.7 | ) |  | (12.6 | ) |  | (21.7 | ) |  | (8.0 | )
Settlements with taxing authorities | — |  |  | — |  |  | (16.1 | ) |  | — |  |  | — |  |  | (9.0 | ) |  | — |  |  | — |  |  | (6.9 | )
Balance, December 31 (c) |  | $0.7 |  |  |  | $23.5 |  |  |  | $66.7 |  |  |  | $— |  |  |  | $10.9 |  |  |  | $33.0 |  |  |  | $0.7 |  |  |  | $12.6 |  |  |  | $33.7 |
(a) | The additions for tax positions of prior years were related to positions taken by Alliant Energy, IPL and WPL on their federal and state tax returns related to the capitalization and dispositions of property.
(b) | In 2012, the reductions for tax positions of prior years were due to the finalization of Alliant Energy’s federal income tax return audits for calendar years 2005 through 2009. In 2011, the reductions for tax positions of prior years were related to guidance published by the IRS clarifying the treatment of repair expenditures for electric distribution property. In 2010, the reductions of tax positions of prior years were primarily related to deductions taken by Alliant Energy, IPL and WPL on their federal and state tax returns that were settled under audit for amounts less than the reductions of tax positions recorded.
(c) | At December 31, 2012 and 2011, $0 and $10 million, respectively, of uncertain tax positions balances for both Alliant Energy and IPL included amounts recorded in regulatory liability accounts.
At December 31, 2012, 2011 and 2010, there were no penalties accrued related to uncertain tax positions. Additional information regarding uncertain tax positions at December 31 is as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Tax positions favorably impacting future effective tax rates for continuing operations |  | $0.7 |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $0.7 |  |  |  | $— |  |  |  | $— |
Interest accrued | — |  |  | 0.4 |  |  | 0.7 |  |  | — |  |  | 0.4 |  |  | 0.7 |  |  | — |  |  | — |  |  | — |
Schedule Of Open Tax Years | Open tax years - Tax years that remain subject to the statute of limitations are as follows:
Major Jurisdiction |  | Alliant Energy |  | IPL |  | WPL
Consolidated federal income tax returns (a) |  | 2005 | - | 2011 |  | 2005 | - | 2011 |  | 2005 | - | 2011
Consolidated Iowa income tax returns (b) |  | 2005 | - | 2011 |  | 2005 | - | 2011 |  | 2005 | - | 2011
Wisconsin income tax returns |  | 2005 | - | 2008 |  | N/A |  | 2005 | - | 2008
Wisconsin combined tax returns |  | 2009 | - | 2011 |  | 2009 | - | 2011 |  | 2009 | - | 2011
(a) | 2005 through 2010 are effectively settled. The statute of limitations for 2005 through 2008 has been extended to June 30, 2013. The statute of limitations for 2009 through 2011 expires three years from the extended due date of the federal tax return.
(b) | 2005 through 2008 are open for federal audit adjustments only.

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- Definition Tabular disclosure of tax positions taken in the tax returns filed or to be filed for which it is more likely than not that the tax position will not be sustained upon examination by taxing authorities (i.e., uncertain tax positions) and other types of income tax contingencies, including: (1) the policy on classification of interest and penalties; (2) a tabular reconciliation of the total amounts of unrecognized tax benefits at the beginning and end of the period; the total amount(s) of: (3) unrecognized tax benefits that, if recognized, would affect the effective tax rate, and (4) interest and penalties recognized in each of the income statement and balance sheet; (5) for positions for which it is reasonably possible that the total amounts unrecognized will significantly change within 12 months of the reporting date the: (i) nature of the uncertainty, (ii) nature of the event that could occur that would cause the change, and (iii) an estimate of the range of the reasonably possible change or a statement that an estimate of the range cannot be made; and (6) a description of tax years that remain subject to examination by major tax jurisdictions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 48 -Paragraph 21 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition Tabular disclosure of tax credit carryforwards available to reduce future taxable income, including amounts, expiration dates, limitations on use and the related deferred tax assets and valuation allowances. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 17 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 43 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Carryforwards -URI http://asc.fasb.org/extlink&oid=6506874 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 48 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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