Investment Securities - Amortized Cost and Fair Value of Available for Sale Securities and Held to Maturity Securities by Contractual Maturity (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Available for Sale
Due in one year or less - Amortized Cost	$ 6,774
Due after one through five years - Amortized Cost	29,991
Due after five through ten years - Amortized Cost	48,498
Due after ten years - Amortized Cost	173,149
Total debt securities with a single maturity date - Amortized Cost	258,412
Total Investment Securities - Amortized Cost	598,706
Due in one year or less - Fair Value	6,836
Due after one through five years - Fair Value	30,598
Due after five through ten years - Fair Value	50,344
Due after ten years - Fair Value	179,013
Total debt securities with a single maturity date - Fair Value	266,791
Total Investment Securities - Fair Value	615,184
Held to Maturity
Due in one year or less - Amortized Cost	3,366
Due after one through five years - Amortized Cost	18,228
Due after five through ten years - Amortized Cost	84,112
Due after ten years - Amortized Cost	67,374
Total debt securities with a single maturity date - Amortized Cost	173,080
Total Investment Securities - Amortized Cost	598,903	559,378
Due in one year or less - Fair Value	3,367
Due after one through five years - Fair Value	18,517
Due after five through ten years - Fair Value	85,868
Due after ten years - Fair Value	69,071
Total debt securities with a single maturity date - Fair Value	176,823
Investment securities held to maturity - fair value	612,162	560,847
U.S. Government-sponsored mortgage-backed securities
Available for Sale
Without single maturity date - Amortized Cost	338,588
Without single maturity date - Fair Value	346,687
Held to Maturity
Without single maturity date - Amortized Cost	425,823
Total Investment Securities - Amortized Cost	425,823	413,437
Without single maturity date - Fair Value	435,339
Investment securities held to maturity - fair value	435,339	414,935
Equity securities
Available for Sale
Without single maturity date - Amortized Cost	1,706
Without single maturity date - Fair Value	$ 1,706

Available-For-Sale Securities, Debt Maturity, with Single Maturity Date, Amortized Cost

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- Definition

Available-For-Sale Securities, Debt Maturity, with Single Maturity Date, Fair Value

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No definition available.

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- Definition

Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized and fair value hedge accounting adjustments, maturing in the next rolling twelve months following the latest balance sheet presented.

+ References

No definition available.

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized and fair value hedge accounting adjustments, maturing after the tenth rolling twelve months following the latest balance sheet presented.

+ References

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized and fair value hedge accounting adjustments, maturing in the sixth rolling twelve months through the tenth rolling twelve months following the latest balance sheet presented.

+ References

No definition available.

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized and fair value hedge accounting adjustments, maturing in the second rolling twelve months through the fifth rolling twelve months following the latest balance sheet presented

+ References

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- Definition

Held-To-Maturity Securities, Debt Maturities, with Single Maturity Date, Net Carrying Amount

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No definition available.

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- Definition

Held-To-Maturity Securities, Debt Maturity, with Single Maturity Date, Fair Value

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No definition available.

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- Definition

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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-Name Accounting Standards Codification

-Topic 320

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-Section 50

-Paragraph 2

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- Definition

Amount after adjustments of available-for-sale debt securities at cost, maturing in the next rolling twelve months following the latest balance sheet. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments and fair value hedge accounting adjustments. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Fair value of available-for-sale debt securities maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Amount after adjustments of available-for-sale debt securities at cost, maturing after the tenth rolling twelve months following the latest balance sheet. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Fair value of available-for-sale debt securities maturing after the tenth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount after adjustments of available-for-sale debt securities at cost, maturing in the sixth through tenth rolling twelve months following the latest balance sheet. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Fair value of available-for-sale debt securities maturing in the sixth through tenth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Amount after adjustments of available-for-sale debt securities at cost, maturing in the second through fifth rolling twelve months following the latest balance sheet. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Fair value of available-for-sale debt securities maturing in the second through fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of available-for-sale debt securities at cost, net of adjustments, that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the cost over several maturity groupings. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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-Name Accounting Standards Codification

-Topic 320

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- Definition

Amount of available-for-sale debt securities at fair value that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the fair value over several maturity groupings.

+ References

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

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-Name Accounting Standards Codification

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- Definition

Amount of debt securities categorized neither as held-to-maturity nor trading.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 320

-Section 50

-Paragraph 2

-Subparagraph (b)-(g)

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- Definition

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

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-Subparagraph (f)

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-Name Accounting Standards Codification

-Topic 944

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-Subparagraph (SX 210.9-03.6)

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- Definition

Fair value of held-to-maturity debt securities maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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Fair value of held-to-maturity debt securities maturing after the tenth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Fair value of held-to-maturity debt securities maturing in the sixth through tenth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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Fair value of held-to-maturity debt securities maturing in the second through fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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Amount of held-to-maturity debt securities at fair value that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the fair value over several maturity groupings.

+ References

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- Definition

Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, over several maturity groupings.

+ References

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- Definition

Fair value of investments in debt securities classified as held-to-maturity.

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