Acquisition of TelWorx Communications LLC - Allocation of Purchase Price for Assets from Date of Acquisition (Detail) (TelWorx Communications LLC [Member], USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Tangible assets:
Purchase price allocation, Assets	$ 17,448
Intangible assets:
Purchase price allocation, Assets	17,448
Purchase price allocation, Assets	17,448
Purchase price allocation, Liabilities	1,368
Purchase price allocation Assets and Liabilities Assumed, Net	16,080
Accounts Receivable [Member]
Tangible assets:
Purchase price allocation, Assets	1,370
Intangible assets:
Purchase price allocation, Assets	1,370
Purchase price allocation, Assets	1,370
Inventories [Member]
Tangible assets:
Purchase price allocation, Assets	1,378
Intangible assets:
Purchase price allocation, Assets	1,378
Purchase price allocation, Assets	1,378
Prepaid Expenses and Other Current Assets [Member]
Tangible assets:
Purchase price allocation, Assets	9
Intangible assets:
Purchase price allocation, Assets	9
Purchase price allocation, Assets	9
Assets [Member]
Tangible assets:
Purchase price allocation, Assets	248
Intangible assets:
Purchase price allocation, Assets	248
Purchase price allocation, Assets	248
Tangible Assets [Member]
Tangible assets:
Purchase price allocation, Assets	3,005
Intangible assets:
Purchase price allocation, Assets	3,005
Purchase price allocation, Assets	3,005
Goodwill [Member]
Tangible assets:
Purchase price allocation, Assets	12,550
Intangible assets:
Purchase price allocation, Assets	12,550
Purchase price allocation, Assets	12,550
Trade names [Member]
Tangible assets:
Purchase price allocation, Assets	1,259
Intangible assets:
Purchase price allocation, Assets	1,259
Purchase price allocation, Assets	1,259
Technology-Based Intangible Assets [Member]
Tangible assets:
Purchase price allocation, Assets	470
Intangible assets:
Purchase price allocation, Assets	470
Purchase price allocation, Assets	470
Customer relationships [Member]
Tangible assets:
Purchase price allocation, Assets	117
Intangible assets:
Purchase price allocation, Assets	117
Purchase price allocation, Assets	117
Order or Production Backlog [Member]
Tangible assets:
Purchase price allocation, Assets	33
Intangible assets:
Purchase price allocation, Assets	33
Purchase price allocation, Assets	33
Non-compete [Member]
Tangible assets:
Purchase price allocation, Assets	14
Intangible assets:
Purchase price allocation, Assets	14
Purchase price allocation, Assets	14
Intangible Assets [Member]
Tangible assets:
Purchase price allocation, Assets	14,443
Intangible assets:
Purchase price allocation, Assets	14,443
Purchase price allocation, Assets	14,443
Assets Held under Capital Leases [Member]
Intangible assets:
Purchase price allocation, Liabilities	(37)
Accounts Payable [Member]
Intangible assets:
Purchase price allocation, Liabilities	(1,213)
Accrued Liabilities [Member]
Intangible assets:
Purchase price allocation, Liabilities	(118)
Estimated Fair Value [Member]
Tangible assets:
Purchase price allocation, Assets	18,402
Intangible assets:
Purchase price allocation, Assets	18,402
Purchase price allocation, Assets	18,402
Purchase price allocation, Liabilities	1,255
Purchase price allocation Assets and Liabilities Assumed, Net	17,147
Estimated Fair Value [Member] | Accounts Receivable [Member]
Tangible assets:
Purchase price allocation, Assets	1,575
Intangible assets:
Purchase price allocation, Assets	1,575
Purchase price allocation, Assets	1,575
Estimated Fair Value [Member] | Inventories [Member]
Tangible assets:
Purchase price allocation, Assets	1,843
Intangible assets:
Purchase price allocation, Assets	1,843
Purchase price allocation, Assets	1,843
Estimated Fair Value [Member] | Prepaid Expenses and Other Current Assets [Member]
Tangible assets:
Purchase price allocation, Assets	9
Intangible assets:
Purchase price allocation, Assets	9
Purchase price allocation, Assets	9
Estimated Fair Value [Member] | Assets [Member]
Tangible assets:
Purchase price allocation, Assets	248
Intangible assets:
Purchase price allocation, Assets	248
Purchase price allocation, Assets	248
Estimated Fair Value [Member] | Tangible Assets [Member]
Tangible assets:
Purchase price allocation, Assets	3,675
Intangible assets:
Purchase price allocation, Assets	3,675
Purchase price allocation, Assets	3,675
Estimated Fair Value [Member] | Goodwill [Member]
Tangible assets:
Purchase price allocation, Assets	9,491
Intangible assets:
Purchase price allocation, Assets	9,491
Purchase price allocation, Assets	9,491
Estimated Fair Value [Member] | Trade names [Member]
Tangible assets:
Purchase price allocation, Assets	1,527
Intangible assets:
Purchase price allocation, Assets	1,527
Purchase price allocation, Assets	1,527
Estimated Fair Value [Member] | Technology-Based Intangible Assets [Member]
Tangible assets:
Purchase price allocation, Assets	458
Intangible assets:
Purchase price allocation, Assets	458
Purchase price allocation, Assets	458
Estimated Fair Value [Member] | Customer relationships [Member]
Tangible assets:
Purchase price allocation, Assets	2,898
Intangible assets:
Purchase price allocation, Assets	2,898
Purchase price allocation, Assets	2,898
Estimated Fair Value [Member] | Order or Production Backlog [Member]
Tangible assets:
Purchase price allocation, Assets	91
Intangible assets:
Purchase price allocation, Assets	91
Purchase price allocation, Assets	91
Estimated Fair Value [Member] | Non-compete [Member]
Tangible assets:
Purchase price allocation, Assets	262
Intangible assets:
Purchase price allocation, Assets	262
Purchase price allocation, Assets	262
Estimated Fair Value [Member] | Intangible Assets [Member]
Tangible assets:
Purchase price allocation, Assets	14,727
Intangible assets:
Purchase price allocation, Assets	14,727
Purchase price allocation, Assets	14,727
Estimated Fair Value [Member] | Assets Held under Capital Leases [Member]
Intangible assets:
Purchase price allocation, Liabilities	(57)
Estimated Fair Value [Member] | Accounts Payable [Member]
Intangible assets:
Purchase price allocation, Liabilities	(1,113)
Estimated Fair Value [Member] | Accrued Liabilities [Member]
Intangible assets:
Purchase price allocation, Liabilities	(85)
Provisional Adjustments [Member]
Tangible assets:
Purchase price allocation, Assets	(954)
Intangible assets:
Purchase price allocation, Assets	(954)
Purchase price allocation, Assets	(954)
Purchase price allocation, Liabilities	113
Purchase price allocation Assets and Liabilities Assumed, Net	(1,067)
Provisional Adjustments [Member] | Accounts Receivable [Member]
Tangible assets:
Purchase price allocation, Assets	(205)
Intangible assets:
Purchase price allocation, Assets	(205)
Purchase price allocation, Assets	(205)
Provisional Adjustments [Member] | Inventories [Member]
Tangible assets:
Purchase price allocation, Assets	(465)
Intangible assets:
Purchase price allocation, Assets	(465)
Purchase price allocation, Assets	(465)
Provisional Adjustments [Member] | Prepaid Expenses and Other Current Assets [Member]
Tangible assets:
Purchase price allocation, Assets	0
Intangible assets:
Purchase price allocation, Assets	0
Purchase price allocation, Assets	0
Provisional Adjustments [Member] | Assets [Member]
Tangible assets:
Purchase price allocation, Assets	0
Intangible assets:
Purchase price allocation, Assets	0
Purchase price allocation, Assets	0
Provisional Adjustments [Member] | Tangible Assets [Member]
Tangible assets:
Purchase price allocation, Assets	(670)
Intangible assets:
Purchase price allocation, Assets	(670)
Purchase price allocation, Assets	(670)
Provisional Adjustments [Member] | Goodwill [Member]
Tangible assets:
Purchase price allocation, Assets	3,059
Intangible assets:
Purchase price allocation, Assets	3,059
Purchase price allocation, Assets	3,059
Provisional Adjustments [Member] | Trade names [Member]
Tangible assets:
Purchase price allocation, Assets	(268)
Intangible assets:
Purchase price allocation, Assets	(268)
Purchase price allocation, Assets	(268)
Provisional Adjustments [Member] | Technology-Based Intangible Assets [Member]
Tangible assets:
Purchase price allocation, Assets	12
Intangible assets:
Purchase price allocation, Assets	12
Purchase price allocation, Assets	12
Provisional Adjustments [Member] | Customer relationships [Member]
Tangible assets:
Purchase price allocation, Assets	(2,781)
Intangible assets:
Purchase price allocation, Assets	(2,781)
Purchase price allocation, Assets	(2,781)
Provisional Adjustments [Member] | Order or Production Backlog [Member]
Tangible assets:
Purchase price allocation, Assets	(58)
Intangible assets:
Purchase price allocation, Assets	(58)
Purchase price allocation, Assets	(58)
Provisional Adjustments [Member] | Non-compete [Member]
Tangible assets:
Purchase price allocation, Assets	(248)
Intangible assets:
Purchase price allocation, Assets	(248)
Purchase price allocation, Assets	(248)
Provisional Adjustments [Member] | Intangible Assets [Member]
Tangible assets:
Purchase price allocation, Assets	(284)
Intangible assets:
Purchase price allocation, Assets	(284)
Purchase price allocation, Assets	(284)
Provisional Adjustments [Member] | Assets Held under Capital Leases [Member]
Intangible assets:
Purchase price allocation, Liabilities	20
Provisional Adjustments [Member] | Accounts Payable [Member]
Intangible assets:
Purchase price allocation, Liabilities	(100)
Provisional Adjustments [Member] | Accrued Liabilities [Member]
Intangible assets:
Purchase price allocation, Liabilities	$ (33)