Pension And Other Postretirement Benefits (Components Of Net Benefit Costs) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Defined Benefit Plan Disclosure [Line Items]
Amortization of net loss	$ (1,007)	$ (406)	$ (3,021)	$ (1,217)
Webster Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	7	43	22	131
Interest cost	1,827	1,866	5,480	5,597
Expected return on plan assets	(2,517)	(2,638)	(7,551)	(7,913)
Amortization of prior service cost	0	0	0	0
Amortization of net loss	1,525	669	4,577	2,006
Net periodic benefit cost (income) recognized in net income	842	(60)	2,528	(179)
Webster SERP [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	79	78	237	262
Expected return on plan assets	0	0	0	0
Amortization of prior service cost	0	0	0	0
Amortization of net loss	18	(16)	53	0
Net periodic benefit cost (income) recognized in net income	97	62	290	262
Other Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	44	54	132	162
Expected return on plan assets	0	0	0	0
Amortization of prior service cost	18	18	54	54
Amortization of net loss	26	18	77	49
Net periodic benefit cost (income) recognized in net income	$ 88	$ 90	$ 263	$ 265