Segment and Related Information - Segment Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Interest income	$ 241,318	$ 254,330	$ 261,378
Interest expense	17,526	28,991	50,750
Net interest income	223,792	225,339	210,628
(Credit) provision for credit loss expense	(2,219)	17,213	1,366
Noninterest income	78,849	73,860	75,433
Noninterest expense	190,287	184,320	181,834
Income Before Income Tax Expense	114,573	97,666	102,861
Income tax expense	25,182	19,924	21,016
Net Income Attributable to Noncontrolling Interests and Tompkins Financial Corporation	89,391	77,742	81,845
Less: Net income attributable to noncontrolling interests	127	154	127
Net Income Attributable to Tompkins Financial Corporation	89,264	77,588	81,718
Depreciation and amortization	10,250	10,192	10,044
Assets	7,819,982	7,622,171	6,725,623
Goodwill	92,447	92,447	92,447
Other intangibles, net	3,643	4,905	6,223
Net Loans and Leases	5,032,624	5,208,658	4,877,658
Deposits	6,791,435	6,437,752	5,212,921
Total equity	728,941	717,689	663,054	$ 620,871
Banking
Segment Reporting Information [Line Items]
Goodwill	64,369	64,369	64,369
Insurance
Segment Reporting Information [Line Items]
Goodwill	19,867	19,867	19,867
Wealth Management
Segment Reporting Information [Line Items]
Goodwill	8,211	8,211	8,211
Operating Segments | Banking
Segment Reporting Information [Line Items]
Interest income	241,322	254,330	261,378
Interest expense	17,541	28,995	50,753
Net interest income	223,781	225,335	210,625
(Credit) provision for credit loss expense	(2,219)	17,213	1,366
Noninterest income	25,944	26,015	29,054
Noninterest expense	152,624	147,680	145,102
Income Before Income Tax Expense	99,320	86,457	93,211
Income tax expense	21,257	17,033	18,598
Net Income Attributable to Noncontrolling Interests and Tompkins Financial Corporation	78,063	69,424	74,613
Less: Net income attributable to noncontrolling interests	127	154	127
Net Income Attributable to Tompkins Financial Corporation	77,936	69,270	74,486
Depreciation and amortization	9,987	9,912	9,778
Assets	7,794,561	7,564,342	6,671,409
Goodwill	64,370	64,370	64,370
Other intangibles, net	1,571	2,418	3,215
Net Loans and Leases	5,032,624	5,208,658	4,877,658
Deposits	6,802,852	6,449,289	5,223,893
Total equity	664,800	660,334	608,901
Operating Segments | Insurance
Segment Reporting Information [Line Items]
Interest income	11	4	3
Interest expense	0	0	0
Net interest income	11	4	3
(Credit) provision for credit loss expense	0	0	0
Noninterest income	35,430	31,930	31,501
Noninterest expense	26,857	25,941	25,908
Income Before Income Tax Expense	8,584	5,993	5,596
Income tax expense	2,326	1,625	1,426
Net Income Attributable to Noncontrolling Interests and Tompkins Financial Corporation	6,258	4,368	4,170
Less: Net income attributable to noncontrolling interests	0	0	0
Net Income Attributable to Tompkins Financial Corporation	6,258	4,368	4,170
Depreciation and amortization	208	229	225
Assets	42,879	41,812	41,841
Goodwill	19,866	19,866	19,866
Other intangibles, net	2,004	2,398	2,860
Net Loans and Leases	0	0	0
Deposits	0	0	0
Total equity	33,171	31,455	32,204
Operating Segments | Wealth Management
Segment Reporting Information [Line Items]
Interest income	0	0	0
Interest expense	0	0	0
Net interest income	0	0	0
(Credit) provision for credit loss expense	0	0	0
Noninterest income	19,727	18,131	17,001
Noninterest expense	13,058	12,915	12,947
Income Before Income Tax Expense	6,669	5,216	4,054
Income tax expense	1,599	1,266	992
Net Income Attributable to Noncontrolling Interests and Tompkins Financial Corporation	5,070	3,950	3,062
Less: Net income attributable to noncontrolling interests	0	0	0
Net Income Attributable to Tompkins Financial Corporation	5,070	3,950	3,062
Depreciation and amortization	55	51	41
Assets	33,735	28,616	24,313
Goodwill	8,211	8,211	8,211
Other intangibles, net	68	89	148
Net Loans and Leases	0	0	0
Deposits	0	0	0
Total equity	30,970	25,900	21,949
Intercompany
Segment Reporting Information [Line Items]
Interest income	(15)	(4)	(3)
Interest expense	(15)	(4)	(3)
Net interest income	0	0	0
(Credit) provision for credit loss expense	0	0	0
Noninterest income	(2,252)	(2,216)	(2,123)
Noninterest expense	(2,252)	(2,216)	(2,123)
Income Before Income Tax Expense	0	0	0
Income tax expense	0	0	0
Net Income Attributable to Noncontrolling Interests and Tompkins Financial Corporation	0	0	0
Less: Net income attributable to noncontrolling interests	0	0	0
Net Income Attributable to Tompkins Financial Corporation	0	0	0
Depreciation and amortization	0	0	0
Assets	(51,193)	(12,599)	(11,940)
Goodwill	0	0	0
Other intangibles, net	0	0	0
Net Loans and Leases	0	0	0
Deposits	(11,417)	(11,537)	(10,972)
Total equity	$ 0	$ 0	$ 0