Regulatory and Capital Requirements - Schedule of Actual Capital Positions and Ratios under Banking Regulations (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Total Risk-based Capital
Risk-based Capital Actual, Amount	$ 2,084,531	$ 1,910,304
Risk-based Capital Actual, Ratio	12.15%	12.02%
Risk-based Capital Minimum Capital Requirements, Amount	$ 1,480,006	$ 1,271,171
Risk-based Capital Minimum Capital Requirements, Ratio	8.625%	8.00%
Common Equity Tier 1 Capital
Common Equity Tier 1 Capital, Amount	$ 1,590,825	$ 1,431,973
Common Equity Tier 1 Capital, Ratio	9.27%	9.01%
Common Equity Tier 1 Capital	$ 879,424	$ 715,034
Common Equity Tier 1 Capital Minimum Capital Requirements, Ratio	5.125%	4.50%
Tier 1 Risk-based Capital
Tier 1 Risk-based Capital Actual, Amount	$ 1,698,767	$ 1,543,937
Tier 1 Risk-based Capital Actual, Ratio	9.90%	9.72%
Tier 1 Risk-based Capital Minimum Capital Requirements, Amount	$ 1,136,816	$ 953,378
Tier 1 Risk-based Capital Minimum Capital Requirements, Ratio	6.625%	6.00%
Tier 1 Leverage Capital
Tier 1 Leverage Capital Actual, Amount	$ 1,698,767	$ 1,543,937
Tier 1 Leverage Capital Actual, Ratio	7.74%	7.90%
Tier 1 Leverage Capital Minimum Capital Requirements, Amount	$ 878,244	$ 781,388
Tier 1 Leverage Capital Minimum Capital Requirements, Ratio	4.00%	4.00%
Valley National Bank [Member]
Total Risk-based Capital
Risk-based Capital Actual, Amount	$ 2,023,857	$ 1,826,420
Risk-based Capital Actual, Ratio	11.82%	11.53%
Risk-based Capital Minimum Capital Requirements, Amount	$ 1,476,767	$ 1,266,942
Risk-based Capital Minimum Capital Requirements, Ratio	8.625%	8.00%
Risk-based Capital To Be Well Capitalized Under Prompt Corrective Action Provision, Amount	$ 1,712,193	$ 1,583,677
Risk-based Capital To Be Well Capitalized Under Prompt Corrective Action Provision, Ratio	10.00%	10.00%
Common Equity Tier 1 Capital
Common Equity Tier 1 Capital, Amount	$ 1,807,201	$ 1,618,053
Common Equity Tier 1 Capital, Ratio	10.55%	10.22%
Common Equity Tier 1 Capital	$ 877,499	$ 712,655
Common Equity Tier 1 Capital Minimum Capital Requirements, Ratio	5.125%	4.50%
Common Equity Tier 1 Capital To Be Well Capitalized Under Prompt Corrective Action Provision, Amount	$ 1,112,926	$ 1,029,390
Common Equity Tier 1 Capital To Be Well Capitalized Under Prompt Corrective Action Provision, Ratio	6.50%	6.50%
Tier 1 Risk-based Capital
Tier 1 Risk-based Capital Actual, Amount	$ 1,807,201	$ 1,618,053
Tier 1 Risk-based Capital Actual, Ratio	10.55%	10.22%
Tier 1 Risk-based Capital Minimum Capital Requirements, Amount	$ 1,134,328	$ 950,206
Tier 1 Risk-based Capital Minimum Capital Requirements, Ratio	6.625%	6.00%
Tier 1 Risk-based Capital To Be Well Capitalized Under Prompt Corrective Action Provision, Amount	$ 1,369,755	$ 1,266,942
Tier 1 Risk-based Capital To Be Well Capitalized Under Prompt Corrective Action Provision, Ratio	8.00%	8.00%
Tier 1 Leverage Capital
Tier 1 Leverage Capital Actual, Amount	$ 1,807,201	$ 1,618,053
Tier 1 Leverage Capital Actual, Ratio	8.25%	8.29%
Tier 1 Leverage Capital Minimum Capital Requirements, Amount	$ 876,026	$ 780,831
Tier 1 Leverage Capital Minimum Capital Requirements, Ratio	4.00%	4.00%
Tier 1 Leverage Capital To Be Well Capitalized Under Prompt Corrective Action Provision, Amount	$ 1,095,032	$ 976,039
Tier 1 Leverage Capital To Be Well Capitalized Under Prompt Corrective Action Provision, Ratio	5.00%	5.00%