Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2018

Schedule of Defined Benefit Plans Disclosures



	U.S. Pension Benefits						Non-U.S. Pension Benefits						Other Benefits						Total
	2018			2017			2018			2017			2018			2017			2018			2017
Change in benefit obligation:
Benefit obligation at beginning of year	$	142,571		$	138,155		$	918,478		$	838,277		$	2,673		$	2,985		$	1,063,722		$	979,417
Service cost, gross	1,090			565			30,721			29,600			—			—			31,811			30,165
Interest cost	4,242			4,374			8,630			8,511			66			70			12,938			12,955
Actuarial losses (gains)	(10,019		)	6,979			(40,469		)	33,036			(167		)	18			(50,655		)	40,033
Plan amendments and other	—			—			974			(15,153		)	(8		)	137			966			(15,016		)
Benefits paid	(7,682		)	(7,502		)	(36,379		)	(30,356		)	(378		)	(537		)	(44,439		)	(38,395		)
Impact of foreign currency	—			—			(17,860		)	54,563			—			—			(17,860		)	54,563
Benefit obligation at end of year	$	130,202		$	142,571		$	864,095		$	918,478		$	2,186		$	2,673		$	996,483		$	1,063,722
Change in plan assets:
Fair value of plan assets at beginning of year	$	111,567		$	104,103		$	808,215		$	716,169		$	—		$	—		$	919,782		$	820,272
Actual return on plan assets	(8,419		)	14,869			(34,102		)	49,055			—			—			(42,521		)	63,924
Employer contributions	75			97			26,032			22,961			227			400			26,334			23,458
Plan participants’ contributions	—			—			15,176			13,503			151			137			15,327			13,640
Benefits paid	(7,682		)	(7,502		)	(36,379		)	(30,356		)	(378		)	(537		)	(44,439		)	(38,395		)
Impact of foreign currency and other	—			—			(11,532		)	36,883			—			—			(11,532		)	36,883
Fair value of plan assets at end of year	$	95,541		$	111,567		$	767,410		$	808,215		$	—		$	—		$	862,951		$	919,782
Funded status	$	(34,661	)	$	(31,004	)	$	(96,685	)	$	(110,263	)	$	(2,186	)	$	(2,673	)	$	(133,532	)	$	(143,940	)

Schedule of Amounts Recognized in Balance Sheet



	U.S. Pension Benefits						Non-U.S. Pension Benefits						Other Benefits						Total
	2018			2017			2018			2017			2018			2017			2018			2017
Other non-current assets	$	—		$	—		$	46,014		$	40,493		$	—		$	—		$	46,014		$	40,493
Accrued and other liabilities	(110		)	(88		)	(4,884		)	(4,990		)	(431		)	(411		)	(5,425		)	(5,489		)
Pension and other post-retirement liabilities	(34,551		)	(30,916		)	(137,815		)	(145,766		)	(1,755		)	(2,262		)	(174,121		)	(178,944		)
Accumulated other comprehensive loss (income)	61,344			61,819			260,820			254,870			(910		)	(2,365		)	321,254			314,324
Total	$	26,683		$	30,815		$	164,135		$	144,607		$	(3,096	)	$	(5,038	)	$	187,722		$	170,384

Schedule of Net Periodic Benefit Cost Not yet Recognized



	U.S. Pension Benefits		Non-U.S. Pension Benefits			Other Benefits			Total			Total, After Tax
Plan amendments and prior service cost	$	—	$	(22,541	)	$	—		$	(22,541	)	$	(17,873	)
Actuarial losses (gains)	61,344		283,361			(910		)	343,795			266,332
Total	$	61,344	$	260,820		$	(910	)	$	321,254		$	248,459

Schedule of Changes in Accumulated Postemployment Benefit Obligations



	U.S. Pension Benefits			Non-U.S. Pension Benefits			Other Benefits			Total			Total, After Tax
Net actuarial losses (gains)	$	5,329		$	24,637		$	(167	)	$	29,799		$	23,326
Plan amendment	—			974			—			974			780
Amortization of:
Actuarial (losses) gains	(5,804		)	(21,521		)	1,250			(26,075		)	(20,173		)
Plan amendments and prior service cost	—			6,947			372			7,319			5,807
Impact of foreign currency	—			(5,087		)	—			(5,087		)	(3,522		)
Total	$	(475	)	$	5,950		$	1,455		$	6,930		$	6,218

Schedule of Assumptions Used in Computing Benefit Obligation



	U.S.				Non-U.S.
	2018		2017		2018		2017
Discount rate	4.11	%	3.49	%	1.22	%	0.97	%
Compensation increase rate	n/a		n/a		0.87	%	0.87	%
Expected long-term rate of return on plan assets	6.50	%	6.50	%	3.84	%	3.86	%

Schedule of Assumptions Used in Computing Pension Cost



	U.S.						Non-U.S.
	2018		2017		2016		2018		2017		2016
Discount rate	3.49	%	3.97	%	4.27	%	0.97	%	0.98	%	1.31	%
Compensation increase rate	n/a		n/a		n/a		0.87	%	0.85	%	1.03	%
Expected long-term rate of return on plan assets	6.50	%	6.75	%	7.25	%	3.86	%	4.09	%	4.58	%

Schedule of Net Benefit Costs [Table Text Block]

Net periodic pension cost and net periodic post-retirement benefit for the defined benefit plans and U.S. post-retirement plan include the following components for the years ended December 31:



	U.S.									Non-U.S.									Other Benefits									Total
	2018			2017			2016			2018			2017			2016			2018			2017			2016			2018			2017			2016
Service cost, net	$	1,090		$	565		$	432		$	15,545		$	16,341		$	16,804		$	—		$	—		$	—		$	16,635		$	16,906		$	17,236
Interest cost on projected benefit obligations	4,242			4,374			4,428			8,630			8,511			10,664			66			70			76			12,938			12,955			15,168
Expected return on plan assets	(6,929		)	(6,737		)	(7,781		)	(31,005		)	(30,349		)	(33,168		)	—			—			—			(37,934		)	(37,086		)	(40,949		)
Recognition of actuarial losses/(gains) and prior service costs	5,804			6,556			7,606			14,575			16,247			12,923			(1,623		)	(2,674		)	(4,567		)	18,756			20,129			15,962
Settlement charge	—			—			7,963			—			—			—			—			—			—			—			—			7,963
Net periodic pension cost / (benefit)	$	4,207		$	4,758		$	12,648		$	7,745		$	10,750		$	7,223		$	(1,557	)	$	(2,604	)	$	(4,491	)	$	10,395		$	12,904		$	15,380

Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year



	U.S. Pension Benefits		Non-U.S. Pension Benefits			Other Benefits			Total
Plan amendments and prior service costs	$	—	$	(6,798	)	$	—		$	(6,798	)
Actuarial losses (gains)	2,374		21,630			(691		)	23,313
Total	$	2,374	$	14,832		$	(691	)	$	16,515

Schedule of Allocation of Plan Assets



	December 31, 2018								December 31, 2017
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Observable Inputs for Identical Assets (Level 2)		Unobservable Inputs (Level 3)		Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Observable Inputs for Identical Assets (Level 2)		Unobservable Inputs (Level 3)		Total
Asset Category:
Cash and Cash Equivalents	$	111,484	$	—	$	—	$	111,484	$	154,751	$	—	$	—	$	154,751
Equity Securities:
Mettler-Toledo Stock	2,436		—		—		2,436		3,154		—		—		3,154
Equity Mutual Funds:
U.S.⁽¹⁾	4,989		22,569		—		27,558		6,011		27,984		—		33,995
International⁽²⁾	68,544		45,892		—		114,436		80,836		61,341		—		142,177
Emerging Markets⁽³⁾	95,146		692		—		95,838		100,346		1,096		—		101,442
Fixed Income Securities:
Corporate/Government Bonds⁽⁴⁾	71,644		—		—		71,644		72,334		—		—		72,334
Fixed Income Mutual Funds:
Insurance Contracts⁽⁵⁾	—		22,852		1,461		24,313		—		23,421		1,514		24,935
Core Bond⁽⁶⁾	95,493		54,448		—		149,941		136,157		57,499		—		193,656
Real Asset Mutual Funds:
Real Estate⁽⁷⁾	83,879		13,838		—		97,717		79,218		8,836		—		88,054
Commodities⁽⁸⁾	40,267		—		—		40,267		37,302		—		—		37,302
Other Types of Investments:
Debt Securities ⁽⁹⁾	38,616		—		—		38,616		—		—		—		—
Global Allocation Funds⁽¹⁰⁾	11,195		10,562		—		21,757		11,781		12,545		—		24,326
Insurance Linked Securities⁽¹¹⁾	18,664		—		—		18,664		12,147		—		—		12,147
Total assets in fair value hierarchy	$	642,357	$	170,853	$	1,461	$	814,671	$	694,037	$	192,722	$	1,514	$	888,273
Investments measured at net asset value:
International⁽²⁾							2,792								—
Emerging Markets ⁽³⁾							4,889								5,950
Multi-Strategy Fund of Hedge Funds ⁽¹²⁾							40,599								25,559
Total pension assets at fair value							$	862,951							$	919,782

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation



	Commodities			Insurance Contract			Total
Balance at December 31, 2016	$	5,594		$	1,300		$	6,894
Actual return on plan assets related to assets held at end of year	—			21			21
Sales	(5,711		)	(98		)	(5,809		)
Purchases	—			108			108
Impact of foreign currency	117			183			300
Balance at December 31, 2017	$	—		$	1,514		$	1,514
Actual return on plan assets related to assets held at end of year	—			14			14
Sales	—			(85		)	(85		)
Purchases	—			82			82
Impact of foreign currency	—			(64		)	(64		)
Balance at December 31, 2018	$	—		$	1,461		$	1,461

Schedule of Expected Benefit Payments



	U.S. Pension Benefits		Non-U.S. Pension Benefits		Other Benefits Net of Subsidy		Total
2019	$	8,051	$	43,494	$	431	$	51,976
2020	8,247		43,111		249		51,607
2021	8,396		45,220		231		53,847
2022	8,546		43,543		207		52,296
2023	8,698		44,397		180		53,275
2024-2028	43,532		222,671		666		266,869