Securities (Securities Available for Sale) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	$ 1,609,784	$ 1,680,491
Available-for-sale Debt Securities Gross Unrealized Gain, instant	22,541	22,551
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(20,914)	(38,931)
Securities available for sale	1,611,411	1,664,111
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	867,583	961,442
Available-for-sale Debt Securities Gross Unrealized Gain, instant	7,950	10,640
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(13,067)	(23,674)
Securities available for sale	862,466	948,408
State and Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	376,862	357,013
Available-for-sale Debt Securities Gross Unrealized Gain, instant	14,101	11,450
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(1,466)	(3,993)
Securities available for sale	389,497	364,470
U.S. Government and Government-Sponsored Enterprise Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	339,152	335,671
Available-for-sale Debt Securities Gross Unrealized Gain, instant	467	434
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(5,620)	(10,066)
Securities available for sale	333,999	326,039
US Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	20,903	21,081
Available-for-sale Debt Securities Gross Unrealized Gain, instant	1	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(600)	(967)
Securities available for sale	20,304	20,114
Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized cost	5,284	5,284
Available-for-sale Debt Securities Gross Unrealized Gain, instant	22	27
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(161)	(231)
Securities available for sale	$ 5,145	$ 5,080

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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

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This item represents the cost of debt and equity 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.

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

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