REGULATORY MATTERS (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2013 National Penn Bancshares, Inc. [Member]	Dec. 31, 2012 National Penn Bancshares, Inc. [Member]	Dec. 31, 2013 National Penn Bank [Member]	Dec. 31, 2012 National Penn Bank [Member]
Regulatory Capital Requirements [Abstract]
Required reserve, Federal Reserve Bank	$ 22,888
Average reserve balance, Federal Reserve Bank	46,255
Total capital (to risk-weighted assets) [Abstract]
Total capital		1,018,316	1,056,835	870,973	879,015
Total capital to risk-weighted assets (in hundredths)		16.72%	17.80%	14.40%	15.09%
Total capital for capital adequacy purposes		487,295	475,097	483,796	465,961
Total capital for capital adequacy purposes to risk-weighted assets (in hundredths)		8.00%	8.00%	8.00%	8.00%
Total capital to be well capitalized				604,745	582,452
Total capital to risk-weighted assets (in hundredths)				10.00%	10.00%
Tier I capital (to risk-weighted assets) [Abstract]
Tier I capital		941,926	982,148	795,123	805,738
Tier I capital to risk-weighted assets (in hundredths)		15.46%	16.54%	13.15%	13.83%
Tier I capital for capital adequacy purposes		243,647	237,548	241,898	232,981
Tier I capital for capital adequacy purposes to risk-weighted assets (in hundredths)		4.00%	4.00%	4.00%	4.00%
Tier I capital to be well capitalized				362,847	349,471
Tier I capital to be well capitalized to risk-weighted assets (in hundredths)				6.00%	6.00%
Tier I Capital (to average assets) [Abstract]
Tier I capital		941,926	982,148	795,123	805,738
Tier I capital to average assets (in hundredths)		11.63%	12.16%	9.85%	10.02%
Tier I capital for capital adequacy purposes (average assets)		323,963	323,131	323,030	321,802
Tier I capital for capital adequacy purposes to average assets (in hundredths)		4.00%	4.00%	4.00%	4.00%
Tier I capital to be well capitalized (average assets)				$ 403,788	$ 402,252
Tier I capital to average assets (in hundredths)				5.00%	5.00%

Average reserve balance at the Federal Reserve Bank during the reporting period.

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Amount of reserve required at the Federal Reserve Bank as of the report date.

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The minimum Tier One Capital Ratio (Tier one capital average assets divided by average assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital to be well capitalized divided by average assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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