Derivative Instruments (Tables)

3 Months Ended

Mar. 31, 2013

Derivative Instruments

Schedule of volume activity of natural gas derivatives that is expected to settle or mature each year

Year	Natural Gas Swaps (MMBTUs) (in millions)
2013	2.2
2014	1.3
Total	3.5

Schedule of remaining notional amount of forecasted debt issuances hedged in each year with LIBOR swaptions

Year		LIBOR Swaption Notional Dollar Amount (in thousands)
2013	$	568,621
2014		563,425
2015		470,625
2016		310,533
2017		80,169
Total	$	1,993,373

Schedule of fair value of derivative instruments and their effect on condensed balance sheets.

	Balance Sheet Location		Fair Value
			2013		2012
			(dollars in thousands)
Not designated as hedges:
Assets:
Interest rate options(1)	Other deferred charges	$	26,539	$	25,783
Natural gas swaps	Prepayments and other current assets	$	576	$	—
Liabilities:
Natural gas swaps	Other current liabilities	$	—	$	1,085

⁽¹⁾

Excludes liability associated with cash collateral of $13,360,000 and $8,950,000 as of March 31, 2013 and December 31, 2012, respectively, which is recorded as an offset to the fair value of the swaptions on the unaudited Condensed Balance Sheets.

Schedule of the realized gains and (losses) on derivative instruments recognized in margin

	Statement of Revenues and		Three months ended March 31,
	Expenses Location		2013			2012
			(dollars in thousands)
Designated as hedges:
Natural Gas Swaps	Fuel	$	—		$	(2,407	)
Not Designated as hedges:
Natural Gas Swaps	Fuel		117			—
Natural Gas Swaps	Fuel		(534	)		—
		$	(417	)	$	(2,407	)

Schedule of unrealized gains and (losses) on derivative instruments deferred on the balance sheet

	Balance Sheet Location		2013			2012
			(dollars in thousands)
Not designated as hedges:
Interest rate options	Regulatory asset	$	(69,072	)	$	(74,217	)
Natural gas swaps	Regulatory asset		—			(1,085	)
Natural gas swaps	Regulatory liability		576			—
		$	(68,496	)	$	(75,302	)

Schedule of gross amounts of derivatives and their related offset amounts as permitted by their respective master netting agreements and obligation to return cash collateral

• The following table presents the gross amounts of derivatives and their related offset amounts as permitted by their respective master netting agreements and obligations to return cash collateral at March 31, 2013 and December 31, 2012.

		Gross Amounts of Recognized Assets (Liabilities)		Gross Amounts offset on the Balance Sheet			Cash Collateral			Net Amounts of Assets Presented on the Balance Sheet
Assets:
Natural gas swaps	$	815	$	(239	)	$	—		$	576
Interest rate options	$	26,539	$	—		$	(13,360	)	$	13,179