Retirement Benefits (Tables)

12 Months Ended

Sep. 30, 2019

Defined Contribution Plan [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Amount of Expense Associated with Defined Contribution Plans

		Year Ended September 30,
	2019		2018		2017
Company costs	$	35,510	$	34,084	$	32,008

Defined Benefit Pension Plan [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Periodic Benefit Costs

	Year Ended September 30,
	United States						Other Countries						Total
	2019		2018		2017		2019		2018		2017		2019		2018		2017
Service cost	$	1,451	$	1,643	$	1,675	$	2,036	$	1,124	$	1,133	$	3,487	$	2,767	$	2,808
Interest cost		6,384		6,004		5,757		1,906		1,526		1,208		8,290		7,530		6,965
Expected return on plan assets		(11,986)		(11,614)		(10,529)		(2,638)		(2,780)		(2,605)		(14,624)		(14,394)		(13,134)
Amortization of:
Net losses		617		598		1,854		283		291		514		900		889		2,368
Net prior service cost		709		709		383		-		-		-		709		709		383
Net periodic (benefit) cost	$	(2,825)	$	(2,660)	$	(860)	$	1,587	$	161	$	250	$	(1,238)	$	(2,499)	$	(610)

Schedule of Changes in Projected Benefit Obligations, Fair Value of Plan Assets, and Funded Status of Plan

	At or for the Year Ended September 30,
	United States				Other Countries				Total
	2019		2018		2019		2018		2019		2018
Changes in projected benefit obligation:
Projected benefit obligation at beginning of year	$	150,032	$	161,130	$	103,485	$	66,369	$	253,517	$	227,499
Plan amendment		-		-		601		-		601		-
Obligation assumed in L'Orange acquisition		-		-		-		39,257		-		39,257
Service cost		1,451		1,643		2,036		1,124		3,487		2,767
Interest cost		6,384		6,004		1,906		1,526		8,290		7,530
Net actuarial losses (gains)		23,841		(13,128)		22,174		(383)		46,015		(13,511)
Contribution by participants		-		34		9		9		9		43
Benefits paid		(6,113)		(5,651)		(3,181)		(2,888)		(9,294)		(8,539)
Foreign currency exchange rate changes		-		-		(5,495)		(1,529)		(5,495)		(1,529)
Projected benefit obligation at end of year	$	175,595	$	150,032	$	121,535	$	103,485	$	297,130	$	253,517
Changes in fair value of plan assets:
Fair value of plan assets at beginning of year	$	165,342	$	160,332	$	62,380	$	64,380	$	227,722	$	224,712
Actual return on plan assets		11,327		10,627		5,121		1,407		16,448		12,034
Contributions by the Company		-		-		1,697		994		1,697		994
Contributions by plan participants		-		34		9		9		9		43
Benefits paid		(6,113)		(5,651)		(3,181)		(2,888)		(9,294)		(8,539)
Foreign currency exchange rate changes		-		-		(2,449)		(1,522)		(2,449)		(1,522)
Fair value of plan assets at end of year	$	170,556	$	165,342	$	63,577	$	62,380	$	234,133	$	227,722
Net (under)/over funded status at end of year	$	(5,039)	$	15,310	$	(57,958)	$	(41,105)	$	(62,997)	$	(25,795)

Schedule of Accumulated Benefit Obligations In Excess of and Less Than Fair Value of Plan Assets

	Plans with accumulated benefit obligation in excess of plan assets				Plans with accumulated benefit obligation less than plan assets
	At September 30,				At September 30,
	2019		2018		2019		2018
Projected benefit obligation	$	(286,495)	$	(65,938)	$	(10,635)	$	(187,579)
Accumulated benefit obligation		(284,368)		(65,915)		(9,605)		(184,864)
Fair value of plan assets		222,661		23,385		11,472		204,337

Schedule of Amounts Recognized in Balance Sheet and Other Comprehensive Income (Loss)

	At or for the Year Ended September 30,
	United States				Other Countries				Total
	2019		2018		2019		2018		2019		2018
Amounts recognized in statement of financial position consist of:
Other non-current assets	$	-	$	17,068	$	838	$	1,090	$	838	$	18,158
Accrued liabilities		-		-		(1,539)		(1,322)		(1,539)		(1,322)
Other non-current liabilities		(5,039)		(1,758)		(57,256)		(40,873)		(62,295)		(42,631)
Net (under)/over funded status at end of year	$	(5,039)	$	15,310	$	(57,957)	$	(41,105)	$	(62,996)	$	(25,795)
Amounts recognized in accumulated other ‎comprehensive income consist of:
Unrecognized net prior service cost	$	5,750	$	6,459	$	579	$	-	$	6,329	$	6,459
Unrecognized net losses		28,167		4,285		32,641		14,529		60,808		18,814
Total amounts recognized		33,917		10,744		33,220		14,529		67,137		25,273
Deferred taxes		(11,577)		(5,892)		(10,029)		(5,081)		(21,606)		(10,973)
Amounts recognized in accumulated other comprehensive income	$	22,340	$	4,852	$	23,191	$	9,448	$	45,531	$	14,300

Schedule of Changes in Plan Assets and Benefit Obligations Recorded in Other Comprehensive Income (Loss)

	Year Ended September 30,
	United States				Other Countries				Total
	2019		2018		2019		2018		2019		2018
Accumulated other comprehensive losses at beginning of year	$	10,744	$	24,192	$	14,529	$	14,198	$	25,273	$	38,390
Net loss (gain)		24,499		(12,141)		19,691		990		44,190		(11,151)
Prior service cost due to plan amendment		-		-		601		-		601	$	-
Amortization of:
Net losses		(617)		(598)		(283)		(292)		(900)		(890)
Prior service cost		(709)		(709)		-		-		(709)		(709)
Foreign currency exchange rate changes		-		-		(1,318)		(367)		(1,318)		(367)
Accumulated other comprehensive losses at end of year	$	33,917	$	10,744	$	33,220	$	14,529	$	67,137	$	25,273

Schedule of Amounts Expected to be Amortized from Accumulated Other Comprehensive Income (Loss) and Reported as a Component of Net Periodic Benefit Cost During the Next Fiscal Year

	United States		Other Countries		Total
Prior service cost	$	936	$	22	$	958
Net actuarial losses		1,430		1,017		2,447

Schedule of Expected Benefit Payments

Year Ending September 30,	United States		Other Countries		Total
2020	$	7,170	$	3,631	$	10,801
2021		7,823		3,363		11,186
2022		8,383		3,239		11,622
2023		8,924		3,805		12,729
2024		9,385		3,695		13,080
2025 – 2029		51,139		19,494		70,633

Schedule of Allocation of Plan Assets, Actual and Target Allocations

	At September 30,
	2019				2018
	Percentage of Plan Assets	Target Allocation Ranges			Percentage of Plan Assets	Target Allocation Ranges
United States:
Asset Class
Equity Securities	60.6%	41.4%	-	81.4%	65.1%	41.5%	-	81.5%
Debt Securities	37.9%	28.6%	-	48.6%	33.1%	28.5%	-	48.5%
Other	1.5%	0.0%			1.8%	0.0%
	100.0%				100.0%
United Kingdom:
Asset Class
Equity Securities	41.6%	30.0%	-	60.0%	44.8%	30.0%	-	60.0%
Debt Securities	57.8%	45.0%	-	70.0%	54.8%	45.0%	-	70.0%
Other	0.6%	0.0%			0.4%	0.0%
	100.0%				100.0%
Japan:
Asset Class
Equity Securities	41.4%	36.0%	-	44.0%	41.0%	36.0%	-	44.0%
Debt Securities	57.7%	55.0%	-	63.0%	58.1%	55.0%	-	63.0%
Other	0.9%	0.0%	-	2.0%	0.9%	0.0%	-	2.0%
	100.0%				100.0%

Schedule of Allocation of Plan Assets, Fair Value Hierarchy

	At September 30, 2019
	Level 1				Level 2				Level 3
	United States		Other Countries		United States		Other Countries		United States		Other Countries		Total
Asset Category:
Cash and cash equivalents	$	2,568	$	418	$	-	$	-	$	-	$	-	$	2,986
Mutual funds:
U.S. corporate bond fund		64,514		-		-		-		-		-		64,514
U.S. equity large cap fund		56,829		-		-		-		-		-		56,829
International equity large cap growth fund		46,645		-		-		-		-		-		46,645
Pooled funds:
Japanese equity securities		-		-		-		2,518		-		-		2,518
International equity securities		-		-		-		2,226		-		-		2,226
Japanese fixed income securities		-		-		-		4,915		-		-		4,915
International fixed income securities		-		-		-		1,710		-		-		1,710
Global target return equity/bond fund		-		-		-		12,488		-		-		12,488
Index linked U.K. equity fund		-		-		-		3,738		-		-		3,738
Index linked international equity fund		-		-		-		5,438		-		-		5,438
Index linked U.K. corporate bonds fund		-		-		-		16,737		-		-		16,737
Index linked U.K. government securities fund		-		-		-		5,491		-		-		5,491
Index linked U.K. long-term government securities fund		-		-		-		7,898		-		-		7,898
Total assets	$	170,556	$	418	$	-	$	63,159	$	-	$	-	$	234,133
	At September 30, 2018
	Level 1				Level 2				Level 3
	United States		Other Countries		United States		Other Countries		United States		Other Countries		Total
Asset Category:
Cash and cash equivalents	$	2,908	$	317	$	-	$	-	$	-	$	-	$	3,225
Mutual funds:
U.S. corporate bond fund		54,699		-		-		-		-		-		54,699
U.S. equity large cap fund		60,176		-		-		-		-		-		60,176
International equity large cap growth fund		47,559		-		-		-		-		-		47,559
Pooled funds:
Japanese equity securities		-		-		-		2,506		-		-		2,506
International equity securities		-		-		-		2,214		-		-		2,214
Japanese fixed income securities		-		-		-		4,968		-		-		4,968
International fixed income securities		-		-		-		1,730		-		-		1,730
Global target return equity/bond fund		-		-		-		12,495		-		-		12,495
Index linked U.K. equity fund		-		-		-		4,326		-		-		4,326
Index linked international equity fund		-		-		-		5,973		-		-		5,973
Index linked U.K. corporate bonds fund		-		-		-		16,121		-		-		16,121
Index linked U.K. government securities fund		-		-		-		4,913		-		-		4,913
Index linked U.K. long-term government securities fund		-		-		-		6,817		-		-		6,817
Total assets	$	165,342	$	317	$	-	$	62,063	$	-	$	-	$	227,722

Other Postretirement Benefit Plans [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Periodic Benefit Costs

	Year Ended September 30,
	2019		2018		2017
Service cost	$	5	$	7	$	14
Interest cost		1,154		1,165		1,244
Amortization of:
Net losses		55		94		201
Net prior service benefit		(5)		(158)		(158)
Curtailment gain		-		(330)		-
Net periodic cost	$	1,209	$	778	$	1,301

Schedule of Actuarial Assumptions Used

	2019		2018		2017
Weighted-average discount rate used to determine benefit obligation at September 30	3.05	%	4.30	%	3.78	%
Weighted-average discount rate used to determine net periodic benefit cost for years ended September 30	4.30		3.80		3.63

Schedule of Changes in Projected Benefit Obligations, Fair Value of Plan Assets, and Funded Status of Plan

	Year Ended September 30,
	2019		2018
Changes in accumulated postretirement benefit obligation:
Accumulated postretirement benefit obligation at beginning of year	$	27,985	$	32,252
Service cost		5		7
Interest cost		1,154		1,165
Premiums paid by plan participants		1,192		1,311
Net actuarial gains		(373)		(2,716)
Benefits paid		(3,292)		(3,707)
Curtailment		-		(330)
Foreign currency exchange rate changes		-		3
Accumulated postretirement benefit obligation at end of year	$	26,671	$	27,985
Changes in fair value of plan assets:
Fair value of plan assets at beginning of year	$	-	$	-
Contributions by the company		2,100		2,396
Premiums paid by plan participants		1,192		1,311
Benefits paid		(3,292)		(3,707)
Fair value of plan assets at end of year	$	-	$	-
Funded status at end of year	$	(26,671)	$	(27,985)

Schedule of Amounts Recognized in Balance Sheet and Other Comprehensive Income (Loss)

	Year Ended September 30,
	2019		2018
Amounts recognized in statement of financial position consist of:
Accrued liabilities	$	(2,048)	$	(2,249)
Other non-current liabilities		(24,623)		(25,736)
Funded status at end of year	$	(26,671)	$	(27,985)
Amounts recognized in accumulated other comprehensive income consist of:
Unrecognized net prior service (benefit) cost	$	4	$	(1)
Unrecognized net (gains) losses		(3)		425
Total amounts recognized		1		424
Deferred taxes		(414)		(518)
Amounts recognized in accumulated other comprehensive income	$	(413)	$	(94)

Schedule of Changes in Plan Assets and Benefit Obligations Recorded in Other Comprehensive Income (Loss)

	Year Ended September 30,
	2019		2018
Accumulated other comprehensive losses at beginning of year	$	424	$	3,074
Net gain		(373)		(2,654)
Curtailment arising during the period		-		(59)
Amortization of:
Net losses		(55)		(95)
Prior service benefit		5		158
Accumulated other comprehensive losses at end of year	$	1	$	424

Schedule of Health Care Cost Trend Rates

	2019		2018
Health care cost trend rate assumed for next year	6.25	%	6.50	%
Rate to which the cost trend rate is assumed to decline
(the ultimate trend rate)	5.00	%	5.00	%
Year that the rate reaches the ultimate trend rate	2025		2025

Schedule of Health Care Costs Sensitivity

	Change In Health Care Cost Trend Rate
	1% increase		1% decrease
Effect on projected fiscal year 2020 service and interest cost	$	74	$	(65)
Effect on accumulated postretirement benefit obligation at September 30, 2019		2,417		(2,128)

Schedule of Future Postretirement Company Contributions

Year Ending September 30,
2020	$	3,237
2021		3,220
2022		3,183
2023		3,125
2024		3,061
2025 – 2029		13,891

Multiemployer Plans, Pension [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Amounts of Contributions Associated with Multiemployer Defined Benefit Plans

		Year Ended September 30,
	2019		2018		2017
Company contributions	$	252	$	334	$	292

United States [Member] | Defined Benefit Pension Plan [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Actuarial Assumptions Used

	2019		2018		2017
United States:
Weighted-average assumptions to determine benefit obligation at September 30:
Discount rate	3.25	%	4.35	%	3.80	%
Weighted-average assumptions to determine periodic benefit costs for years ended September 30:
Discount rate	4.35		3.80		3.65
Long-term rate of return on plan assets	7.39		7.39		7.38

United Kingdom | Defined Benefit Pension Plan [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Actuarial Assumptions Used

	2019		2018		2017
United Kingdom:
Weighted-average assumptions to determine benefit obligation at September 30:
Discount rate	1.74	%	2.68	%	2.56	%
Rate of compensation increase	3.50		3.60		3.60
Weighted-average assumptions to determine periodic benefit costs for years ended September 30:
Discount rate - service cost	2.70		2.58		2.33
Discount rate - interest cost	2.51		2.36		2.24
Rate of compensation increase	3.60		3.60		3.40
Long-term rate of return on plan assets	4.75		4.75		4.75

Japan | Defined Benefit Pension Plan [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Actuarial Assumptions Used

	2019		2018		2017
Japan:
Weighted-average assumptions to determine benefit obligation at September 30:
Discount rate	0.53	%	0.62	%	0.58	%
Rate of compensation increase	2.00		2.00		2.00
Weighted-average assumptions to determine periodic benefit costs for years ended September 30:
Discount rate - service cost	0.80		0.72		0.59
Discount rate - interest cost	0.42		0.38		0.45
Rate of compensation increase	2.00		2.00		2.02
Long-term rate of return on plan assets	2.50		2.50		2.50

Germany [Member] | Defined Benefit Pension Plan [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Actuarial Assumptions Used

	2019		2018		2017
Germany:
Weighted-average assumptions to determine benefit obligation at September 30:
Discount rate	0.81	%	1.87	%	n/a
Rate of compensation increase	2.50		2.50		n/a
Weighted-average assumptions to determine periodic benefit costs for years ended September 30:
Discount rate - service cost	2.06		2.05		n/a
Discount rate - interest cost	1.53		1.49		n/a
Rate of compensation increase	2.50		2.50		n/a