Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Earnings before income taxes were derived from the following sources:

Components of income tax expense (benefit) were as follows:

Income tax expense in the accompanying consolidated financial statements differed from the expected expense as follows:



	2015			2014		2013
Federal income tax expense at the ‘expected’ rate of 35%	$	289,107		275,602		249,714
Increase (decrease) attributed to:
State income taxes, net of federal benefit	21,613			20,549		16,683
Other, net	(1,061		)	(2,867	)	(1,565	)
Total income tax expense	$	309,659		293,284		264,832
Effective income tax rate	37.5		%	37.2	%	37.1	%

The tax effects of temporary differences that give rise to deferred income tax assets and liabilities at year end were as follows:



	2015			2014
Deferred income tax assets (liabilities):
Inventory costing and valuation methods	$	4,556		4,311
Allowance for doubtful accounts receivable	4,529			4,873
Insurance claims payable	10,930			10,404
Promotions payable	1,738			1,586
Stock-based compensation	8,270			7,837
Federal and state benefit of uncertain tax positions	1,911			1,327
Foreign net operating loss and credit carryforwards	5,155			5,768
Foreign valuation allowances	(3,406		)	(3,007	)
Other, net	1,541			592
Total deferred income tax assets	35,224			33,691
Property and equipment	(90,281		)	(80,458	)
Total deferred income tax liabilities	(90,281		)	(80,458	)
Net deferred income tax liabilities	$	(55,057	)	(46,767	)

A reconciliation of the beginning and ending amount of total gross unrecognized tax benefits was as follows:



	2015			2014
Balance at beginning of year:	$	3,772		3,282
Increase related to prior year tax positions	704			185
Decrease related to prior year tax positions	(43		)	(113	)
Increase related to current year tax positions	984			924
Decrease related to statute of limitation lapses	—			(506	)
Balance at end of year:	$	5,417		3,772