BUSINESS ACQUISITIONS (Details) - USD ($) $ / shares in Units, $ in Thousands					3 Months Ended			6 Months Ended
		Apr. 01, 2015	May. 01, 2014	Jan. 02, 2014	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Apr. 02, 2015
Purchase price allocation [Abstract]
Cash					$ 3,344			$ 3,344
Accounts receivable, net					57,546			57,546
Inventory					9,469			9,469
Property and equipment					15,172			15,172
Goodwill and intangibles	[1]				272,746			272,746
Other assets					1,950			1,950
Assets acquired					360,227			360,227
Current liabilities assumed					30,361			30,361
Non-current liabilities assumed					16,645			16,645
Net assets acquired					313,221			313,221
Goodwill acquired					256,213	$ 253,312		256,213
Goodwill impairment expense						$ 117,600
Pro Forma Information [Abstract]
Net sales					323,688		$ 385,898	666,500	$ 745,325
Net income					$ 7,167		$ 15,661	$ 17,054	$ 27,615
Per share data [Abstract]
Basic earnings (in dollars per share)					$ 0.50		$ 1.06	$ 1.18	$ 1.88
Diluted earnings (in dollars per share)					$ 0.47		$ 1.01	$ 1.12	$ 1.78
Business Acquired during 2014 and 2015 [Member]
Purchase price allocation [Abstract]
Sales from business acquisitions					$ 44,800			$ 88,500
Earnings (loss) before taxes from business acquisitions					2,300			3,700
Minimum [Member]
Purchase price allocation [Abstract]
Discount rate for valuation of acquired intangibles (in hundredths)						10.00%
Maximum [Member]
Purchase price allocation [Abstract]
Discount rate for valuation of acquired intangibles (in hundredths)						13.50%
B27, LLC [Member]
Purchase price allocation [Abstract]
Cash					2,538			2,538
Accounts receivable, net					51,448			51,448
Inventory					6,472			6,472
Property and equipment					14,573			14,573
Goodwill and intangibles	[1]				259,412			259,412
Other assets					1,791			1,791
Assets acquired					336,234			336,234
Current liabilities assumed					26,690			26,690
Non-current liabilities assumed					15,992			15,992
Net assets acquired					293,552			$ 293,552
Purchase price				$ 293,600
Transaction cost				1,000
Purchase price financed under common stock issued				$ 4,000
Number of shares issued on acquisition (in shares)				36,000
Goodwill acquired				$ 178,300
Intangible assets acquired				81,100
Nontax deductible goodwill or intangible assets				$ 154,600
Goodwill impairment expense						$ 105,300
Discount rate for valuation of acquired intangibles (in hundredths)								13.50%
Machinery Tooling and Supply LLC [Member]
Purchase price allocation [Abstract]
Cash					806			$ 806
Accounts receivable, net					5,656			5,656
Inventory					2,522			2,522
Property and equipment					557			557
Goodwill and intangibles	[1]				8,405			8,405
Other assets					59			59
Assets acquired					18,005			18,005
Current liabilities assumed					3,336			3,336
Non-current liabilities assumed					0			0
Net assets acquired					14,669			14,669
Purchase price			$ 14,700
Goodwill acquired			4,300
Intangible assets acquired			$ 4,100
Tool Supply, Inc. [Member]
Purchase price allocation [Abstract]
Cash					0			0
Accounts receivable, net					442			442
Inventory					475			475
Property and equipment					42			42
Goodwill and intangibles	[1]				4,929			4,929
Other assets					100			100
Assets acquired					5,988			5,988
Current liabilities assumed					335			335
Non-current liabilities assumed					653			653
Net assets acquired					$ 5,000			$ 5,000
Purchase price		$ 5,000
Goodwill acquired										$ 2,900
Intangible assets acquired										$ 2,000

[1] The amounts in the table above have not been reduced by the $105.3 million of goodwill impairment charges for B27 recorded in the fourth quarter of 2014.