ServisFirst Bancshares, Inc. Quarterly report pursuant to Section 13 or 15(d)

Note 11 - Fair Value Measurement - Financial Assets and Financial Liabilities Carried at Fair Value on a Recurring Basis (Details)

Note 11 - Fair Value Measurement - Financial Assets and Financial Liabilities Carried at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Available-for-sale securities	$ 657,971	$ 590,184
US Treasury and Government [Member]
Available-for-sale securities	74,707	76,993
Collateralized Mortgage Backed Securities [Member]
Available-for-sale securities	363,425	304,304
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities	84,311	105,994
Corporate Debt Securities [Member]
Available-for-sale securities	135,528	102,893
Fair Value, Recurring [Member]
Available-for-sale securities	657,971	590,184
Fair Value, Recurring [Member] \| US Treasury and Government [Member]
Available-for-sale securities	74,707	76,993
Fair Value, Recurring [Member] \| Collateralized Mortgage Backed Securities [Member]
Available-for-sale securities	363,425	304,304
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities	84,311	105,994
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member]
Available-for-sale securities	135,528	102,893
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Available-for-sale securities	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| US Treasury and Government [Member]
Available-for-sale securities	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Collateralized Mortgage Backed Securities [Member]
Available-for-sale securities	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Corporate Debt Securities [Member]
Available-for-sale securities	0	0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Available-for-sale securities	651,376	583,666
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| US Treasury and Government [Member]
Available-for-sale securities	74,707	76,993
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Collateralized Mortgage Backed Securities [Member]
Available-for-sale securities	363,425	304,304
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities	84,311	105,994
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Corporate Debt Securities [Member]
Available-for-sale securities	128,933	96,375
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Available-for-sale securities	6,595	6,518
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| US Treasury and Government [Member]
Available-for-sale securities	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Collateralized Mortgage Backed Securities [Member]
Available-for-sale securities	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Corporate Debt Securities [Member]
Available-for-sale securities	$ 6,595	$ 6,518