Income Taxes (Schedule of Effective Income Tax Rate Reconciliation) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Provision Income Tax [Line Items]
Statutory Rate Times Pre-tax Income					$ 12,153	$ 9,791	$ 6,660
Add (Subtract) the Tax Effect of:
Income from Tax-exempt Loans and Investments					(1,007)	(780)	(533)
State Income Tax, Net of Federal Tax Effect					494	99	105
General Business Tax Credits					(547)	(370)	(365)
Company Owned Life Insurance					(341)	(385)	(282)
Gain on American Community Bancorp, Inc, Stock					0	(366)	0
Other Differences					(83)	(263)	38
Total	$ 3,229	$ 2,701	$ 5,743	$ 5,229	$ 10,669	$ 7,726	$ 5,623

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other deductions.

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-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

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-SubTopic 10

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