Income Taxes (Tables)

9 Months Ended

Sep. 30, 2016

Income Tax Disclosure [Abstract]

Reconciliation of Unrecognized Tax Benefits

A reconciliation of the amount of unrecognized tax benefit is as follows:

(Millions of Dollars)	Sept. 30, 2016		Dec. 31, 2015
Unrecognized tax benefit — Permanent tax positions	$	3.2	$	2.6
Unrecognized tax benefit — Temporary tax positions	22.7		22.1
Total unrecognized tax benefit	$	25.9	$	24.7

Tax Benefits Associated with NOL and Tax Credit Carryforwards

The unrecognized tax benefit amounts were reduced by the tax benefits associated with net operating loss (NOL) and tax credit carryforwards. The amounts of tax benefits associated with NOL and tax credit carryforwards are as follows:

(Millions of Dollars)	Sept. 30, 2016			Dec. 31, 2015
NOL and tax credit carryforwards	$	(5.7	)	$	(5.0	)