Regulatory Matters (Details) (USD $)	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Regulatory Matters [Abstract]
Past due assets disposition plan amount to be reported, as per previous MOU	$ 1,000,000
Past due assets disposition plan amount to be reported	1,000,000
Components of regulatory capital [Abstract]
Total shareholders' equity	144,085,000	134,975,000	105,032,000	102,627,000
Add (deduct) [Abstract]
Accumulated other comprehensive loss	(6,953,000)	(8,058,000)	(13,065,000)	(11,921,000)
Intangible assets	(3,772,000)	(3,975,000)
Maximum percentage of allowance for loan losses and allowance for unfunded lending commitments (in hundredths)	1.25%
Consolidated [Member]
Total capital to risk-weighted assets [Abstract]
Total risk-based capital	212,720,000	204,663,000
Minimum for Adequately Capitalized Institutions, Amount	109,270,000	111,268,000
Actual, Ratio (in hundredths)	15.57%	14.71%
Minimum for Adequately Capitalized Institutions, Ratio (in hundredths)	8.00%	8.00%
Tier 1 capital to risk-weighted assets [Abstract]
Actual, Amount	195,247,000	185,948,000
Minimum for Adequately Capitalized Institutions, Amount	54,635,000	55,634,000
Actual, Ratio (in hundredths)	14.29%	13.37%
Minimum for Adequately Capitalized Institutions, Ratio (in hundredths)	4.00%	4.00%
Tier 1 capital to average assets [Abstract]
Tier 1 capital	195,247,000	185,948,000
Minimum for Adequately Capitalized Institutions, Amount	82,248,000	92,026,000
Actual, Ratio (in hundredths)	9.50%	8.08%
Minimum for Adequately Capitalized Institutions, Ratio (in hundredths)	4.00%	4.00%
Components of regulatory capital [Abstract]
Total shareholders' equity	144,085,000	134,975,000
Add (deduct) [Abstract]
Qualifying trust preferred securities	48,668,000	47,678,000
Accumulated other comprehensive loss	6,953,000	8,058,000
Intangible assets	(3,772,000)	(3,975,000)
Disallowed capitalized mortgage loan servicing rights	(687,000)	(788,000)
Tier 1 capital	195,247,000	185,948,000
Qualifying trust preferred securities	0	990,000
Allowance for loan losses and allowance for unfunded lending commitments limited to 1.25% of total risk-weighted assets	17,473,000	17,725,000
Total risk-based capital	212,720,000	204,663,000
Actual, minimum board imposed and/or ratios necessary to be well capitalized [Abstract]
Total Capital to Risk-Weighted Assets (in hundredths)	15.57%	14.71%
Tier 1 Capital to Average Total Assets (in hundredths)	9.50%	8.08%
Independent Bank [Member]
Total capital to risk-weighted assets [Abstract]
Total risk-based capital	215,128,000	207,553,000
Minimum for Adequately Capitalized Institutions, Amount	109,051,000	111,063,000
Minimum for Well Capitalized Institutions, Amount	136,313,000	138,829,000
Actual, Ratio (in hundredths)	15.78%	14.95%
Minimum for Adequately Capitalized Institutions, Ratio (in hundredths)	8.00%	8.00%
Minimum for Well-Capitalized Institutions, Ratio (in hundredths)	10.00%	10.00%
Tier 1 capital to risk-weighted assets [Abstract]
Actual, Amount	197,688,000	189,777,000
Minimum for Adequately Capitalized Institutions, Amount	54,525,000	55,531,000
Minimum for Well-Capitalized Institutions, Amount	81,788,000	83,297,000
Actual, Ratio (in hundredths)	14.50%	13.67%
Minimum for Adequately Capitalized Institutions, Ratio (in hundredths)	4.00%	4.00%
Minimum for Well Capitalized Institutions, Ratio (in hundredths)	6.00%	6.00%
Tier 1 capital to average assets [Abstract]
Tier 1 capital	197,688,000	189,777,000
Minimum for Adequately Capitalized Institutions, Amount	82,166,000	91,919,000
Minimum for Well-Capitalized Institutions, Amount	102,707,000	114,899,000
Actual, Ratio (in hundredths)	9.62%	8.26%
Minimum for Adequately Capitalized Institutions, Ratio (in hundredths)	4.00%	4.00%
Minimum for Well-Capitalized Institutions, Ratio (in hundredths)	5.00%	5.00%
Components of regulatory capital [Abstract]
Total shareholders' equity	195,095,000	186,384,000
Add (deduct) [Abstract]
Qualifying trust preferred securities	0	0
Accumulated other comprehensive loss	7,052,000	8,156,000
Intangible assets	(3,772,000)	(3,975,000)
Disallowed capitalized mortgage loan servicing rights	(687,000)	(788,000)
Tier 1 capital	197,688,000	189,777,000
Qualifying trust preferred securities	0	0
Allowance for loan losses and allowance for unfunded lending commitments limited to 1.25% of total risk-weighted assets	17,440,000	17,776,000
Total risk-based capital	$ 215,128,000	$ 207,553,000
Actual, minimum board imposed and/or ratios necessary to be well capitalized [Abstract]
Total Capital to Risk-Weighted Assets (in hundredths)	15.78%	14.95%
Tier 1 Capital to Average Total Assets (in hundredths)	9.62%	8.26%
Board Established Ratios [Member]
Total capital to risk-weighted assets [Abstract]
Actual, Ratio (in hundredths)	11.00%
Tier 1 capital to average assets [Abstract]
Actual, Ratio (in hundredths)	8.00%
Actual, minimum board imposed and/or ratios necessary to be well capitalized [Abstract]
Total Capital to Risk-Weighted Assets (in hundredths)	11.00%
Tier 1 Capital to Average Total Assets (in hundredths)	8.00%
Minimum Ratio To Be Well Capitalized [Member]
Total capital to risk-weighted assets [Abstract]
Actual, Ratio (in hundredths)	10.00%
Tier 1 capital to average assets [Abstract]
Actual, Ratio (in hundredths)	5.00%
Actual, minimum board imposed and/or ratios necessary to be well capitalized [Abstract]
Total Capital to Risk-Weighted Assets (in hundredths)	10.00%
Tier 1 Capital to Average Total Assets (in hundredths)	5.00%