CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Operating Activities
Net income	$ 153.1	$ 188.3
Adjustments to reconcile net income to net cash provided by operating activities
Discontinued operations, net of tax	0.1	(6.1)
Depreciation and amortization expense	71.3	60.9
Recoveries and refunds of regulatory assets and liabilities	54.1	16.5
Net unrealized gains on energy contracts	(19.7)	(65.2)
Bad debt expense	19.3	9.3
Pension and other postretirement expense	7.2	15.9
Pension and other postretirement contributions	(68.6)	(63.2)
Deferred income taxes and investment tax credits	90.2	68.3
Equity income, net of dividends	(3.9)	(4.4)
Termination of tolling agreement with Fox Energy Company LLC	0	(50.0)
Other	1.1	6.3
Changes in working capital
Collateral on deposit	(37.0)	15.4
Accounts receivable and accrued unbilled revenues	(531.5)	(182.8)
Inventories	121.6	137.9
Other current assets	(71.7)	45.4
Accounts payable	272.1	24.7
Temporary LIFO liquidation credit	150.9	83.2
Other current liabilities	54.7	19.2
Net cash provided by operating activities	263.3	319.6
Investing Activities
Capital expenditures	(159.6)	(147.0)
Capital contributions to equity method investments	(5.1)	(1.7)
Acquisition of Fox Energy Company LLC	0	(391.6)
Grant received related to Crane Creek wind project	0	69.0
Other	1.4	(1.9)
Net cash used for investing activities	(163.3)	(473.2)
Financing Activities
Short-term debt, net	(4.1)	74.0
Borrowing on term credit facility	0	200.0
Repayment of long-term debt	0	(22.0)
Proceeds from stock option exercises	0.4	6.4
Shares purchased for stock-based compensation	(9.8)	(2.0)
Payment of dividends
Preferred stock of subsidiary	(0.8)	(0.8)
Common stock	(54.1)	(50.1)
Other	(3.7)	(8.3)
Net cash (used for) provided by financing activities	(72.1)	197.2
Change in cash and cash equivalents - continuing operations	27.9	43.6
Change in cash and cash equivalents - discontinued operations
Net cash provided by (used for) operating activities	6.4	(0.6)
Net cash provided by investing activities	0	1.6
Net change in cash and cash equivalents	34.3	44.6
Cash and cash equivalents at beginning of period	22.3	27.4
Cash and cash equivalents at end of period	56.6	72.0
Supplemental Cash Flow Information
Cash paid for interest	13.4	4.8
Cash received for income taxes	$ (62.7)	$ (1.0)