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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

+ References

+ Details

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- References

No definition available.

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- Definition

Year ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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Employee Benefit Plans - Assumptions Used in Determining Benefit Obligations and Net Periodic Benefit Expense (Detail)	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assumed health care cost trend rates at December 31:
Health care cost trend rate assumed for next year	6.00%		5.70%	6.00%	6.20%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate)	4.50%		4.50%	4.50%	4.50%
Year that the rate reaches the ultimate trend rate			2037	2037	2037
Pension Plans [Member] \| People's Qualified Plan [Member] \| Qualified Plan [Member]
Weighted-average assumptions used to determine benefit obligations at December 31:
Discount rate:	4.41%		3.38%	4.41%	3.74%
Weighted-average assumptions used to determine net periodic benefit (income) expense for the years ended December 31:
Discount rate:	4.34%	3.74%	4.41%		4.41%
Expected return on plan assets			7.25%	7.25%	7.25%
Pension Plans [Member] \| First Connecticut Qualified Plan [Member] \| Qualified Plan [Member]
Weighted-average assumptions used to determine benefit obligations at December 31:
Discount rate:	4.41%		3.39%	4.41%
Weighted-average assumptions used to determine net periodic benefit (income) expense for the years ended December 31:
Discount rate:			4.41%	4.35%
Expected return on plan assets			6.00%	6.00%
Pension Plans [Member] \| United Financial Qualified Plan [Member] \| Qualified Plan [Member]
Weighted-average assumptions used to determine benefit obligations at December 31:
Discount rate:			3.42%
Weighted-average assumptions used to determine net periodic benefit (income) expense for the years ended December 31:
Discount rate:			3.33%
Expected return on plan assets			5.25%
Pension Plans [Member] \| Chittenden Qualified Plan [Member] \| Qualified Plan [Member]
Weighted-average assumptions used to determine benefit obligations at December 31:
Discount rate:					3.62%
Weighted-average assumptions used to determine net periodic benefit (income) expense for the years ended December 31:
Discount rate:					4.16%
Pension Plans [Member] \| Suffolk Qualified Plan [Member] \| Qualified Plan [Member]
Weighted-average assumptions used to determine benefit obligations at December 31:
Discount rate:					3.72%
Weighted-average assumptions used to determine net periodic benefit (income) expense for the years ended December 31:
Discount rate:					4.24%
Other Postretirement Plans [Member] \| People's Qualified Plan [Member]
Weighted-average assumptions used to determine benefit obligations at December 31:
Discount rate:	4.40%		3.40%	4.40%	3.70%
Weighted-average assumptions used to determine net periodic benefit (income) expense for the years ended December 31:
Discount rate:			4.40%	3.70%	4.40%