Fair Value - Summary of Additional Information about Unobservable Inputs Used in Fair Value Measurement (Detail) - Fair Value, Measurements, Nonrecurring [Member] - Level 3 [Member] $ in Thousands	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Impaired Real Estate Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value	$ 13,647
Alternative Investment, Valuation Technique [Extensible List]	eqbk:SalesComparisonApproachMember
Impaired Real Estate Loans [Member] | Minimum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range	0.20
Impaired Real Estate Loans [Member] | Maximum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range	0.24
Impaired Real Estate Loans [Member] | Weighted Average [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range	0.02
Impaired Other Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value	$ 14,263
Alternative Investment, Valuation Technique [Extensible List]	eqbk:MultipleOfEarningsOrDiscountedCashFlowsMember
Range	5.3
Impaired Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value		$ 13,059
Alternative Investment, Valuation Technique [Extensible List]		eqbk:SalesComparisonApproachMember
Impaired Loans [Member] | Minimum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range		0.04
Impaired Loans [Member] | Maximum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range		0.22
Impaired Loans [Member] | Weighted Average [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Range		0.13