Business Segment Information - Operating Results of Business Segments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Jul. 31, 2012	Apr. 30, 2012	Jan. 31, 2012	Oct. 31, 2011	Jul. 31, 2011	Apr. 30, 2011	Jan. 31, 2011	Oct. 31, 2010	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2010
Segment Reporting Disclosure [Line Items]
REVENUES	$ 384,891	$ 379,719	$ 365,449	$ 376,777	$ 361,094	$ 340,188	$ 340,867	$ 309,767	$ 1,506,836	$ 1,351,916	$ 1,193,578
Income (loss) from operations	2,625	2,162	4,032	(11,062)	(818)	319	5,817	4,340	(2,243)	9,658	831
Depreciation and amortization									16,648	20,952	33,341
Severance and other charges										1,053	4,742
Telecom Platform Services [Member]
Segment Reporting Disclosure [Line Items]
REVENUES									1,477,091	1,316,601	1,150,150
Income (loss) from operations									5,945	21,608	14,405
Depreciation and amortization									14,208	17,628	29,220
Severance and other charges										926	1,570
Consumer Phone Services [Member]
Segment Reporting Disclosure [Line Items]
REVENUES									19,307	26,440	37,173
Income (loss) from operations									4,062	7,100	12,476
Depreciation and amortization									9	59	110
Severance and other charges											63
All Other [Member]
Segment Reporting Disclosure [Line Items]
REVENUES									10,438	8,875	6,255
Income (loss) from operations									902	(2,945)	(10,064)
Depreciation and amortization									2,171	2,660	2,969
Severance and other charges											(63)
Corporate [Member]
Segment Reporting Disclosure [Line Items]
Income (loss) from operations									(13,152)	(16,105)	(15,986)
Depreciation and amortization									260	605	1,042
Severance and other charges										$ 127	$ 3,172