CONSOLIDATING GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION (Details) - Summary of Condensed Consolidating Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2016	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
CURRENT ASSETS
Cash and equivalents	$ 68,616	$ 52,001	$ 45,955	$ 92,405	$ 92,405
Accounts receivable, net of allowances	222,768	218,755
Contract costs and recognized income not yet billed, net of progress payments	121,591	103,895
Inventories, net	314,052	325,809
Prepaid and other current assets	63,962	55,086
Assets of discontinued operations	1,301	1,316
Total Current Assets	792,290	756,862
PROPERTY, PLANT AND EQUIPMENT, net	388,149	379,972
GOODWILL	360,255	356,241
INTANGIBLE ASSETS, net	211,681	213,837
INTERCOMPANY RECEIVABLE	0	0
EQUITY INVESTMENTS IN SUBSIDIARIES	0	0
OTHER ASSETS	25,219	22,346
ASSETS OF DISCONTINUED OPERATIONS	2,047	2,175
Total Assets	1,779,641	1,731,433
CURRENT LIABILITIES
Notes payable and current portion of long-term debt	17,776	16,593
Accounts payable and accrued liabilities	270,631	304,808
Liabilities of discontinued operations	1,600	2,229
Total Current Liabilities	290,007	323,630
LONG-TERM DEBT, net of debt discounts	913,838	826,976
INTERCOMPANY PAYABLES	0	0
OTHER LIABILITIES	153,054	146,923
LIABILITIES OF DISCONTINUED OPERATIONS	2,715	3,379
Total Liabilities	1,359,614	1,300,908
Total Shareholders’ Equity	420,027	430,525
Total Liabilities and Shareholders’ Equity	1,779,641	1,731,433
Parent Company [Member]
CURRENT ASSETS
Cash and equivalents	22,699	2,440	4,736	6,813
Accounts receivable, net of allowances	0	0
Contract costs and recognized income not yet billed, net of progress payments	0	0
Inventories, net	0	0
Prepaid and other current assets	34,652	23,493
Assets of discontinued operations	0	0
Total Current Assets	57,351	25,933
PROPERTY, PLANT AND EQUIPMENT, net	1,026	1,108
GOODWILL	0	0
INTANGIBLE ASSETS, net	0	0
INTERCOMPANY RECEIVABLE	553,059	542,297
EQUITY INVESTMENTS IN SUBSIDIARIES	808,951	745,262
OTHER ASSETS	6,854	41,774
ASSETS OF DISCONTINUED OPERATIONS	0	0
Total Assets	1,427,241	1,356,374
CURRENT LIABILITIES
Notes payable and current portion of long-term debt	2,735	2,202
Accounts payable and accrued liabilities	53,989	30,158
Liabilities of discontinued operations	0	0
Total Current Liabilities	56,724	32,360
LONG-TERM DEBT, net of debt discounts	848,004	752,839
INTERCOMPANY PAYABLES	68,957	76,477
OTHER LIABILITIES	33,529	64,173
LIABILITIES OF DISCONTINUED OPERATIONS	0	0
Total Liabilities	1,007,214	925,849
Total Shareholders’ Equity	420,027	430,525
Total Liabilities and Shareholders’ Equity	1,427,241	1,356,374
Guarantor Companies [Member]
CURRENT ASSETS
Cash and equivalents	8,691	10,671	12,893	31,522
Accounts receivable, net of allowances	195,787	178,830
Contract costs and recognized income not yet billed, net of progress payments	121,352	103,879
Inventories, net	240,544	257,929
Prepaid and other current assets	30,343	27,584
Assets of discontinued operations	0	0
Total Current Assets	596,717	578,893
PROPERTY, PLANT AND EQUIPMENT, net	289,928	286,854
GOODWILL	284,875	284,875
INTANGIBLE ASSETS, net	149,073	152,412
INTERCOMPANY RECEIVABLE	799,370	904,840
EQUITY INVESTMENTS IN SUBSIDIARIES	661,936	644,577
OTHER ASSETS	8,999	30,203
ASSETS OF DISCONTINUED OPERATIONS	0	0
Total Assets	2,790,898	2,882,654
CURRENT LIABILITIES
Notes payable and current portion of long-term debt	2,304	3,842
Accounts payable and accrued liabilities	177,862	222,758
Liabilities of discontinued operations	0	0
Total Current Liabilities	180,166	226,600
LONG-TERM DEBT, net of debt discounts	19,424	17,116
INTERCOMPANY PAYABLES	743,810	831,345
OTHER LIABILITIES	105,679	126,956
LIABILITIES OF DISCONTINUED OPERATIONS	0	0
Total Liabilities	1,049,079	1,202,017
Total Shareholders’ Equity	1,741,819	1,680,637
Total Liabilities and Shareholders’ Equity	2,790,898	2,882,654
Non-Guarantor Companies [Member]
CURRENT ASSETS
Cash and equivalents	37,226	38,890	28,326	54,070
Accounts receivable, net of allowances	56,022	61,772
Contract costs and recognized income not yet billed, net of progress payments	239	16
Inventories, net	73,508	67,880
Prepaid and other current assets	14,408	12,488
Assets of discontinued operations	1,301	1,316
Total Current Assets	182,704	182,362
PROPERTY, PLANT AND EQUIPMENT, net	97,195	92,010
GOODWILL	75,380	71,366
INTANGIBLE ASSETS, net	62,608	61,425
INTERCOMPANY RECEIVABLE	292,743	263,480
EQUITY INVESTMENTS IN SUBSIDIARIES	1,805,573	1,740,889
OTHER ASSETS	24,312	9,959
ASSETS OF DISCONTINUED OPERATIONS	2,047	2,175
Total Assets	2,542,562	2,423,666
CURRENT LIABILITIES
Notes payable and current portion of long-term debt	12,737	10,549
Accounts payable and accrued liabilities	83,597	72,843
Liabilities of discontinued operations	1,600	2,229
Total Current Liabilities	97,934	85,621
LONG-TERM DEBT, net of debt discounts	46,410	57,021
INTERCOMPANY PAYABLES	815,214	775,120
OTHER LIABILITIES	22,224	28,428
LIABILITIES OF DISCONTINUED OPERATIONS	2,715	3,379
Total Liabilities	984,497	949,569
Total Shareholders’ Equity	1,558,065	1,474,097
Total Liabilities and Shareholders’ Equity	2,542,562	2,423,666
Elimination [Member]
CURRENT ASSETS
Cash and equivalents	0	0	$ 0	$ 0
Accounts receivable, net of allowances	(29,041)	(21,847)
Contract costs and recognized income not yet billed, net of progress payments	0	0
Inventories, net	0	0
Prepaid and other current assets	(15,441)	(8,479)
Assets of discontinued operations	0	0
Total Current Assets	(44,482)	(30,326)
PROPERTY, PLANT AND EQUIPMENT, net	0	0
GOODWILL	0	0
INTANGIBLE ASSETS, net	0	0
INTERCOMPANY RECEIVABLE	(1,645,172)	(1,710,617)
EQUITY INVESTMENTS IN SUBSIDIARIES	(3,276,460)	(3,130,728)
OTHER ASSETS	(14,946)	(59,590)
ASSETS OF DISCONTINUED OPERATIONS	0	0
Total Assets	(4,981,060)	(4,931,261)
CURRENT LIABILITIES
Notes payable and current portion of long-term debt	0	0
Accounts payable and accrued liabilities	(44,817)	(20,951)
Liabilities of discontinued operations	0	0
Total Current Liabilities	(44,817)	(20,951)
LONG-TERM DEBT, net of debt discounts	0	0
INTERCOMPANY PAYABLES	(1,627,981)	(1,682,942)
OTHER LIABILITIES	(8,378)	(72,634)
LIABILITIES OF DISCONTINUED OPERATIONS	0	0
Total Liabilities	(1,681,176)	(1,776,527)
Total Shareholders’ Equity	(3,299,884)	(3,154,734)
Total Liabilities and Shareholders’ Equity	$ (4,981,060)	$ (4,931,261)