S.Y. Bancorp, Inc. (parent company only) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Assets
Cash on deposit with subsidiary bank	$ 34,519				$ 42,610								$ 34,519	$ 42,610
Securities available for sale (amortized cost of $1,000 in 2012)	490,031				386,440								490,031	386,440
Other assets	51,824				51,407								51,824	51,407
Total assets	2,389,262				2,148,262								2,389,262	2,148,262
Liabilities and stockholders' equity
Other liabilities	26,514				22,949								26,514	22,949
Subordinated debentures					30,900									30,900
Total stockholders' equity	229,444				205,075				187,686				229,444	205,075	187,686	169,861
Total liabilities and stockholders' equity	2,389,262				2,148,262								2,389,262	2,148,262
Securities available for sale, amortized cost	493,066				377,383								493,066	377,383
Condensed Statements of Income
Income - interest income from securities													6,099	5,657	5,174
Income before income taxes	8,699	10,773	9,139	9,787	8,779	9,070	8,602	8,984	7,418	8,246	8,438	7,693	38,398	35,435	31,795
Income tax benefit	2,386	3,091	2,732	3,019	2,265	2,388	2,499	2,482	1,076	2,472	2,441	2,202	11,228	9,634	8,191
Net income	6,313	7,682	6,407	6,768	6,514	6,682	6,103	6,502	6,342	5,774	5,997	5,491	27,170	25,801	23,604
Operating activities
Net income	6,313	7,682	6,407	6,768	6,514	6,682	6,103	6,502	6,342	5,774	5,997	5,491	27,170	25,801	23,604
Adjustments to reconcile net income to net cash provided by operating activities:
Stock compensation expense													1,940	1,481	1,165
Excess tax benefits from share-based compensation arrangements													(265)	(83)	(125)
Depreciation, amortization and accretion, net													7,969	4,964	4,019
Net cash provided by operating activities													58,329	14,796	44,429
Investing activities
Proceeds from maturities of securities available for sale													406,385	452,447	300,620
Cash for acquisition, net of cash acquired													8,963
Net cash used in investing activities													(135,868)	(89,864)	(161,947)
Financing activities
Repayments of subordinated debentures													(30,900)	(10,000)
Excess tax benefit from share-based compensation arrangements													265	83	125
Common stock repurchases													(331)	(205)	(167)
Cash dividends paid													(11,670)	(10,691)	(9,930)
Net cash provided by financing activities													80,606	87,851	130,783
Net increase in cash and cash equivalents													3,067	12,783	13,265
Cash at beginning of year				42,610									42,610
Cash at end of year	34,519				42,610								34,519	42,610
S.Y. Bancorp, Inc.
Assets
Cash on deposit with subsidiary bank	7,453				25,904				24,966				7,453	25,904	24,966
Investment in and receivable from subsidiaries	216,916				204,431								216,916	204,431
Securities available for sale (amortized cost of $1,000 in 2012)					1,018									1,018
Other assets	5,234				4,707								5,234	4,707
Total assets	229,603				236,060								229,603	236,060
Liabilities and stockholders' equity
Other liabilities	159				85								159	85
Subordinated debentures					30,900									30,900
Total stockholders' equity	229,444				205,075								229,444	205,075
Total liabilities and stockholders' equity	229,603				236,060								229,603	236,060
Securities available for sale, amortized cost					1,000									1,000
Condensed Statements of Income
Income - dividends and interest from subsidiaries													30,090	10,090	90
Income - interest income from securities													27	80	104
Income (loss) - other													174	637	(402)
Expenses													7,260	5,130	4,654
Income before income taxes													23,031	5,677	(4,862)
Income tax benefit													(2,583)	(1,674)	(1,889)
Income (loss) before equity in undistributed net income of subsidiary													25,614	7,351	(2,973)
Equity in undistributed net (loss) income of subsidiaries													1,556	18,450	26,577
Net income													27,170	25,801	23,604
Operating activities
Net income													27,170	25,801	23,604
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed net (loss) income of subsidiaries													(1,556)	(18,450)	(26,577)
Decrease (increase) in receivable from subsidiaries													(21,896)	50	(101)
Stock compensation expense													1,940	1,481	1,165
Excess tax benefits from share-based compensation arrangements													(265)	(83)	(125)
Depreciation, amortization and accretion, net													1,396		9
Decrease in other assets													4,453	1,963	3,983
Increase (decrease) in other liabilities													545	28	(17)
Net cash provided by operating activities													11,787	10,790	1,941
Investing activities
Proceeds from maturities of securities available for sale													1,000		3,630
Cash for acquisition, net of cash acquired													8,963
Net cash used in investing activities													9,963		3,630
Financing activities
Repayments of subordinated debentures													(30,900)
Proceeds from stock options													2,435	961	705
Excess tax benefit from share-based compensation arrangements													265	83	125
Common stock repurchases													(331)	(205)	(167)
Cash dividends paid													(11,670)	(10,691)	(9,930)
Net cash provided by financing activities													(40,201)	(9,852)	(9,267)
Net increase in cash and cash equivalents													(18,451)	938	(3,696)
Cash at beginning of year				25,904				24,966				28,662	25,904	24,966	28,662
Cash at end of year	$ 7,453				$ 25,904				$ 24,966				$ 7,453	$ 25,904	$ 24,966