Commitments and Contingencies Commitments and Contingencies (Tables)

6 Months Ended

Jun. 30, 2019

Commitments and Contingencies Disclosure [Abstract]

Schedule of Operating Lease Right-of-Use Assets

Operating lease ROU assets:

(Millions of Dollars)	June 30, 2019
PPAs	$	500.3
Other	48.0
Gross operating lease ROU assets	548.3
Accumulated amortization	(12.8		)
Net operating lease ROU assets	$	535.5

Schedule of Components of Lease Expense

Components of lease expense:

(Millions of Dollars)	Three Months Ended June 30, 2019		Six Months Ended June 30, 2019
Operating leases
PPA capacity payments	$	12.6	$	25.4
Other operating leases (a)	1.3		2.5
Total operating lease expense (b)	$	13.9	$	27.9

^(a)  Includes short-term lease expense of $0.5 million for three months ended June 30, 2019 and $0.9 million for six months ended June 30, 2019.

^(b) 

PPA capacity payments are included in electric fuel and purchased power on the statements of income. Expense for other operating leases is included in O&M expense.

Schedule of Future Commitments under Operating Leases

Future commitments under operating leases as of June 30, 2019:

(Millions of Dollars)	PPA (a) (b) Operating Leases			Other Operating Leases			Total Operating Leases
2019	$	23.1		$	1.7		$	24.8
2020	46.2			3.4			49.6
2021	46.2			3.3			49.5
2022	46.2			3.4			49.6
2023	46.2			3.4			49.6
Thereafter	450.8			54.8			505.6
Total minimum obligation	658.7			70.0			728.7
Interest component of obligation	(170.6		)	(22.6		)	(193.2		)
Present value of minimum obligation	488.1			47.4			535.5
Less current portion							(26.5		)
Noncurrent operating lease liabilities							$	509.0
Weighted-average remaining lease term in years							14.5

^(a)  Amounts do not include PPAs accounted for as executory contracts and/or contingent payments, such as energy payments on renewable PPAs.

^(b)  PPA operating leases contractually expire at various dates through 2033.

Future commitments under operating leases as of Dec. 31, 2018:

(Millions of Dollars)	PPA (a) (b) Operating Leases		Other Operating Leases		Total Operating Leases
2019	$	46.7	$	5.2	$	51.9
2020	46.2		5.2		51.4
2021	46.2		5.1		51.3
2022	46.2		5.1		51.3
2023	46.2		5.1		51.3
Thereafter	450.8		56.3		507.1

^(a)  Amounts do not include PPAs accounted for as executory contracts and/or contingent payments, such as energy payments on renewable PPAs.

^(b) 

PPA operating leases contractually expire at various dates through 2033.