Borrowings and Other Financing Instruments Borrowings and Other Financing Instruments (Tables)

12 Months Ended

Dec. 31, 2019

Dec. 31, 2018

Debt Disclosure [Abstract]

Commercial Paper

Commercial paper outstanding for NSP-Wisconsin was as follows:

(Millions of Dollars, Except Interest Rates)	Three Months Ended Dec. 31, 2019			Year Ended
				2019			2018			2017
Borrowing limit	$	150		$	150		$	150		$	150
Amount outstanding at period end	65			65			51			11
Average amount outstanding	72			51			28			52
Maximum amount outstanding	93			93			103			129
Weighted average interest rate, computed on a daily basis	1.98		%	2.38		%	2.31		%	1.23		%
Weighted average interest rate at period end	1.97			1.97			2.89			1.73

Schedule of Debt To Total Capitalization Ratio

Debt-to-Total Capitalization Ratio(a)				Amount Facility May Be Increased (millions)	Additional Periods for Which a One-Year Extension May Be Requested (b)
2019		2018
48	%	48	%	N/A	1

Credit Facilities

Dec. 31, 2019 (in millions):

Credit Facility (a)		Drawn (b)		Available
$	150	$	65	$	85

^(a)  This credit facility matures in June 2024.

^(b) 

Includes outstanding commercial paper.

other short term debt [Table Text Block]

The following table presents the notes payable of Clearwater Investments, Inc., a NSP-Wisconsin subsidiary, to Xcel Energy Inc.:

(Millions of Dollars, Except Interest Rates)	Dec. 31, 2019		Dec. 31, 2018
Notes payable to affiliates	$	—	$	0.6
Weighted average interest rate	N/A		2.89		%

Schedule of Long-Term Debt

Long-term debt obligations for NSP-Wisconsin as of Dec. 31 (millions of dollars):

Financing Instrument	Interest Rate		Maturity Date	2019			2018
City of La Crosse resource recovery bond	6.00	%	Nov 1, 2021	$	19		$	19
First mortgage bonds	3.30		June 15, 2024	100			100
First mortgage bonds	3.30		June 15, 2024	100			100
First mortgage bonds	6.38		Sept. 1, 2038	200			200
First mortgage bonds	3.70		Oct. 1, 2042	100			100
First mortgage bonds	3.75		Dec. 1, 2047	100			100
First mortgage bonds (a)	4.20		Sept. 1, 2048	200			200
Unamortized discount				(3		)	(3		)
Unamortized debt issuance cost				(8		)	(9		)
Total				$	808		$	807

^(a) 

2018 financing.

Schedule of Maturities of Long-term Debt

Maturities of long-term debt:

(Millions of Dollars)
2020	$	—
2021	19
2022	—
2023	—
2024	200

Dividend Payment Restrictions

Equity to Total Capitalization Ratio - Required Range			Equity to Total Capitalization Ratio Actual
Low		High	2019
51.5	%	N/A	51.8	%

Unrestricted Retained Earnings			Total Capitalization			Limit on Total Capitalization
$	11.5	million	$	1.8	billion	N/A

^(a) NSP-Wisconsin cannot pay annual dividends in excess of approximately $55 million if its average equity-to-total capitalization ratio falls below the commission authorized level.