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Leases (Narrative) (Details) - Sheboygan Falls Energy Facility [Member] - WPL [Member] | 12 Months Ended
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Dec. 31, 2005 lease_renewal_period_option
Leases [Line Items] |
Capital lease, agreement term | 20 years
Capital leases, renewal options (in number of renewal periods) | 2
Capital lease asset amortization term | 20 years

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- Definition Capital Lease Asset Amortization Term + References No definition available. + Details
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- Definition Capital Leases, Agreement Term + References No definition available. + Details
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- Definition Capital Leases, Lease Renewal Period Options + References No definition available. + Details
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- Definition Leases [Line Items] + References No definition available. + Details
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- Details
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- Details
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