Basis of Presentation - Additional Information (Detail) (USD $)	3 Months Ended											12 Months Ended
	Dec. 31, 2013 Manufacturers_Distributors Product	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011	Mar. 31, 2010	Dec. 31, 2013 Location Customer Manufacturers_Distributors Product	Dec. 31, 2012	Dec. 31, 2011	Jun. 30, 2010
Basis Of Presentation [Line Items]
Net sales	$ 1,223,638,000	$ 1,336,676,000	$ 1,274,494,000	$ 1,250,485,000	$ 1,244,074,000	$ 1,288,675,000	$ 1,275,710,000	$ 1,271,647,000				$ 5,085,293,000	$ 5,080,106,000	$ 5,005,501,000
Number of items	140,000											140,000
Number of manufacturers	1,600											1,600
Number of distribution centers												64
Number of reseller customer												25,000
Acquisition purchase price					90,000,000						12,000,000
Acquisition through deferred payments								2,000,000		1,000,000	3,000,000
Acquisition earn out											3,000,000
Payment related to the first earn out									2,000,000
Net of Cash acquired					79,800,000								75,254,000
Indemnification period during acquisition												2 years
Purchase Price	79,800,000											79,800,000
Goodwill	356,811,000				357,226,000							356,811,000	357,226,000
Valuation of goodwill													29,200,000
Intangible assets with definite lives	22,300,000											22,300,000
Liabilities, Intangibles arising from acquisitions	23,689,000				23,264,000							23,689,000	23,264,000
Weighted average useful life of amortizable intangibles												23 years
Assets held for sale current	3,200,000											3,200,000
Weighted average useful lives												0 years	0 years
Acquisition of minority interest															5,000,000
Asset impairment change										1,600,000		1,183,000		1,635,000
Write off of investment	1,200,000
Trademarks and Trade Names [Member]
Basis Of Presentation [Line Items]
Intangible assets with definite lives	2,900,000											2,900,000
Weighted average useful lives												5 years
Customer Lists [Member]
Basis Of Presentation [Line Items]
Intangible assets with definite lives	18,600,000											18,600,000
Weighted average useful lives												23 years
Non-compete Agreements [Member]
Basis Of Presentation [Line Items]
Intangible assets with definite lives	800,000											800,000
Weighted average useful lives												4 years	4 years
O.K.I. Supply Co. [Member]
Basis Of Presentation [Line Items]
Amount payable related to an OKI acquisition					4,500,000								4,500,000
Goodwill	28,700,000											28,700,000
Contribution to the Company's net financial sales												20,500,000
Pro forma net sales													5,200,000	5,200,000
Pro forma net income													$ 112,600,000	$ 113,600,000