10.INCOME TAXES

The income tax expense on income from continuing operations for the years ended December 31, 2014, 2013 and 2012 consisted of the following (in millions):

	Years Ended December 31,
	2014		2013			2012
Current:
Federal	$	45.5	$	(24.3	)	$	38.9
State	3.7		(1.0		)	3.2
Total	49.2		(25.3		)	42.1
Deferred	2.7		57.5			(9.1		)
Total income tax expense	$	51.9	$	32.2		$	33.0

Income tax expense for 2014, 2013, and 2012 differs from amounts computed by applying the statutory federal rate to income from continuing operations before income taxes for the following reasons:

	Years Ended December 31,
	2014		2013		2012
Computed federal income tax expense	35.0%		35.0%		35.0%
State income tax	2.2%		2.9%		0.6%
Deferred tax adjustment	(0.9%	)	0.0%		(1.6%	)
Separation costs	0.0%		0.0%		2.0%
Transaction costs	1.4%		0.0%		0.0%
Unrecognized tax benefits	(0.4%	)	(2.1%	)	1.7%
Valuation allowance	3.3%		0.0%		0.0%
Other — net	1.7%		1.7%		1.1%
Effective income tax rate	42.3%		37.5%		38.8%

The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities at December 31 of each year are as follows (in millions):

	As of December 31,
	2014			2013
Deferred tax assets:
Benefit plans	$	63.6		$	41.8
Insurance reserves	11.4			10.0
Allowance for doubtful accounts	1.4			1.3
Reserves	2.1			6.0
Foreign losses	4.1			3.1
Alternative minimum tax credits	1.5			1.4
Other	0.8			(0.2		)
Total deferred tax assets	84.9			63.4
Valuation allowance	(4.1		)	—
Total Deferred tax assets, net of valuation allowance	80.8			63.4
Deferred tax liabilities:
Basis differences for property and equipment	252.7			278.0
Capital Construction Fund	106.9			83.4
Joint ventures and other investments	7.7			4.6
Deferred revenue	10.1			11.4
Amortization	3.8			3.0
Total deferred tax liabilities	381.2			380.4
Deferred tax liability, net	$	300.4		$	317.0

During 2014, the Company recorded a full valuation allowance against deferred tax assets related to accumulated operating losses of a foreign subsidiary of $4.1 million.

The Company’s income taxes payable has been reduced by the tax benefits from share-based compensation. The Company receives an income tax benefit for exercised stock options calculated as the difference between the fair market value of the stock issued at the time of exercise and the option exercise price, tax effected. The Company also receives an income tax benefit for non-vested stock when it vests, measured as the fair market value of the stock at the time of vesting, tax effected. The net tax benefits from share-based transactions were $0.8 million and $0.6 million for 2014 and 2013, respectively, and the portion of the tax benefit related to the excess of the amount reported as the tax deduction over expense was reflected as an increase to additional paid in capital in the consolidated statements of shareholders’ equity. The Company’s deferred tax liabilities incurred during 2014 and 2013 are primarily due to increased contributions to the CCF (see Note 6).

Unrecognized Tax Benefits: A reconciliation of the beginning and ending amount of gross unrecognized tax benefits is as follows (in millions):

Balance at December 31, 2011	$	2.6
Additions for tax positions of prior years	4.0
Reductions for tax positions of current year	3.7
Reductions for tax positions of prior years	(1.0		)
Reductions for lapse of statute of limitations	(1.0		)
Balance at December 31, 2012	8.3
Additions for tax positions of prior years	2.0
Reductions for lapse of statute of limitations	(3.1		)
Balance at December 31, 2013	7.2
Additions for tax positions of prior years	0.5
Reductions for lapse of statute of limitations	(1.0		)
Balance at December 31, 2014	$	6.7

Of the total unrecognized benefits, $6.7 million, $7.2 million, and $8.3 million at December 31, 2014, 2013 and 2012, respectively, represent the amount that, if recognized, would favorably affect the Company’s effective rate in future periods. The Company does not expect a material change in gross unrecognized benefits in the next twelve months.

The Company recognizes potential accrued interest and penalties related to unrecognized tax benefits in income tax expense. To the extent interest and penalties are not ultimately assessed with respect to the settlement of uncertain tax positions, amounts accrued will be reduced and reflected as a reduction of the overall income tax provision. Interest accrued related to the balance of unrecognized tax benefits totaled $0.2 million, $0.3 million, and $0.4 million as of December 31, 2014, 2013 and 2012, respectively.

The Company is no longer subject to U.S. federal income tax audits for years before 2011, and substantially all material income tax matters have been concluded for years through 2009. The Company is routinely involved in state, local income and excise tax audits.