Goodwill and Other Intangible Assets - Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014
Goodwill [Roll Forward]
Beginning balance	[1]	$ 575,892	$ 428,234
Goodwill from business combinations	[1]	110,447	147,658
Ending balance	[1]	686,339	575,892
Wealth Management [Member]
Goodwill [Roll Forward]
Beginning balance	[1]	20,517	20,517
Goodwill from business combinations	[1]	0	0
Ending balance	[1]	20,517	20,517
Consumer Lending [Member]
Goodwill [Roll Forward]
Beginning balance	[1]	168,922	128,451
Goodwill from business combinations	[1]	30,197	40,471
Ending balance	[1]	199,119	168,922
Commercial Lending
Goodwill [Roll Forward]
Beginning balance	[1]	252,900	174,763
Goodwill from business combinations	[1]	61,360	78,137
Ending balance	[1]	314,260	252,900
Investment Management
Goodwill [Roll Forward]
Beginning balance	[1]	133,553	104,503
Goodwill from business combinations	[1]	18,890	29,050
Ending balance	[1]	$ 152,443	$ 133,553

[1] Valley’s Wealth Management Division is comprised of trust, asset management and insurance services. This reporting unit is included in the Consumer Lending segment for financial reporting purposes.