Condensed Consolidating Financial Information - Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Current assets:
Cash and cash equivalents	$ 65,298	$ 142,597	$ 152,542	$ 75,316
Trade receivables, net	152,084	134,384
Inventories	72,668	55,074
Current income taxes	1,187	329
Other	13,517	11,827
Total current assets	304,754	344,211
Property, plant and equipment, net	206,792	185,718
Other assets:
Goodwill	290,503	178,199	175,586
Intangible assets, net	319,162	143,718
Deferred income taxes	68,059	92,852
Other	49,173	34,321
Total other assets	726,897	449,090
Total assets	1,238,443	979,019	896,306
Current liabilities:
Accounts payable	30,211	25,306
Accrued personnel costs	45,366	52,544
Other accrued liabilities	63,785	51,781
Current portion of long-term debt	7,785	4,250
Total current liabilities	147,147	133,881
Long-term liabilities:
Long-term debt, net	746,716	558,080
Other	41,230	36,776
Total long-term liabilities	787,946	594,856
Total liabilities	935,093	728,737
Redeemable non-controlling interest in consolidated subsidiary	13,363	12,431
Stockholders' equity:
Common stock	74	74
Capital in excess of par value	733,117	728,667
Retained earnings (accumulated deficit)	(441,793)	(489,889)
Treasury stock	(1,411)	(1,001)
Total stockholders' equity	289,987	237,851	102,442	84,410
Total liabilities and stockholders' equity	1,238,443	979,019
Consolidation, Eliminations
Current assets:
Current income taxes	(58,802)	(142,976)
Total current assets	(58,802)	(142,976)
Other assets:
Investments in subsidiaries	(721,760)	(428,708)
Intercompany accounts and notes	(727,747)	(694,839)
Deferred income taxes	(12,077)	(12,115)
Total other assets	(1,461,584)	(1,135,662)
Total assets	(1,520,386)	(1,278,638)
Current liabilities:
Current income taxes	(58,802)	(142,976)
Total current liabilities	(58,802)	(142,976)
Long-term liabilities:
Income taxes	(12,077)
Intercompany accounts and notes	(727,747)	(694,839)
Other		(12,115)
Total long-term liabilities	(739,824)	(706,954)
Total liabilities	(798,626)	(849,930)
Stockholders' equity:
Capital in excess of par value	(764,359)	(540,715)
Retained earnings (accumulated deficit)	42,599	112,007
Total stockholders' equity	(721,760)	(428,708)
Total liabilities and stockholders' equity	(1,520,386)	(1,278,638)
Guarantor Subsidiaries | Reportable Legal Entities
Current assets:
Cash and cash equivalents	27,012	25,819	33,552	70,713
Trade receivables, net	145,443	129,095
Inventories	67,549	52,699
Other	11,975	10,666
Total current assets	251,979	218,279
Property, plant and equipment, net	179,758	164,413
Other assets:
Goodwill	248,016	147,330
Intangible assets, net	282,239	116,479
Investments in subsidiaries		55,844
Intercompany accounts and notes	26,707	57,793
Other	13,293	11,243
Total other assets	570,255	388,689
Total assets	1,001,992	771,381
Current liabilities:
Accounts payable	27,659	23,619
Accrued personnel costs	14,945	14,542
Current income taxes	56,553	137,502
Other accrued liabilities	55,942	39,604
Total current liabilities	155,099	215,267
Long-term liabilities:
Income taxes	12,077
Other	4,581	16,572
Total long-term liabilities	16,658	16,572
Total liabilities	171,757	231,839
Stockholders' equity:
Capital in excess of par value	711,755	486,069
Retained earnings (accumulated deficit)	118,480	53,473
Total stockholders' equity	830,235	539,542
Total liabilities and stockholders' equity	1,001,992	771,381
Non-Guarantor Subsidiaries | Reportable Legal Entities
Current assets:
Cash and cash equivalents	5,304	3,577	5,764	34
Trade receivables, net	6,641	5,289
Inventories	5,119	2,375
Other	1,481	144
Total current assets	18,545	11,385
Property, plant and equipment, net	9,852	9,978
Other assets:
Goodwill	42,487	30,869
Intangible assets, net	36,923	27,239
Deferred income taxes	23,083	25,204
Other	10,922	2,291
Total other assets	113,415	85,603
Total assets	141,812	106,966
Current liabilities:
Accounts payable	1,301	1,114
Accrued personnel costs	519	501
Current income taxes	2,249	5,474
Other accrued liabilities	5,002	6,380
Total current liabilities	9,071	13,469
Long-term liabilities:
Intercompany accounts and notes	211,087	178,179
Other	16,941	13,897
Total long-term liabilities	228,028	192,076
Total liabilities	237,099	205,545
Redeemable non-controlling interest in consolidated subsidiary	13,363	12,431
Stockholders' equity:
Capital in excess of par value	52,429	54,470
Retained earnings (accumulated deficit)	(161,079)	(165,480)
Total stockholders' equity	(108,650)	(111,010)
Total liabilities and stockholders' equity	141,812	106,966
Parent Company | Reportable Legal Entities
Current assets:
Cash and cash equivalents	32,982	113,201	$ 113,226	$ 4,569
Current income taxes	59,989	143,305
Other	61	1,017
Total current assets	93,032	257,523
Property, plant and equipment, net	17,182	11,327
Other assets:
Investments in subsidiaries	721,760	372,864
Intercompany accounts and notes	701,040	637,046
Deferred income taxes	57,053	79,763
Other	24,958	20,787
Total other assets	1,504,811	1,110,460
Total assets	1,615,025	1,379,310
Current liabilities:
Accounts payable	1,251	573
Accrued personnel costs	29,902	37,501
Other accrued liabilities	2,841	5,797
Current portion of long-term debt	7,785	4,250
Total current liabilities	41,779	48,121
Long-term liabilities:
Long-term debt, net	746,716	558,080
Intercompany accounts and notes	516,660	516,660
Other	19,708	18,422
Total long-term liabilities	1,283,084	1,093,162
Total liabilities	1,324,863	1,141,283
Stockholders' equity:
Common stock	74	74
Capital in excess of par value	733,292	728,843
Retained earnings (accumulated deficit)	(441,793)	(489,889)
Treasury stock	(1,411)	(1,001)
Total stockholders' equity	290,162	238,027
Total liabilities and stockholders' equity	$ 1,615,025	$ 1,379,310