FEDERAL INCOME TAX (Reconciliation) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Computed expected income tax expense (benefit)	$ 35,666	$ 16,126	$ (4,451)
Tax-exempt municipal bond interest income	(7,732)	(8,027)	(7,908)
Nontaxable dividend income	(1,053)	(1,004)	(859)
Valuation allowance reduction	(548)	(547)	0
Acquisition related expenses	0	42	860
Other, net	(571)	(728)	(368)
Federal income tax expense (benefit)	$ 25,762	$ 5,862	$ (12,726)

Income Tax Reconciliation, Tax Exempt Income, Dividend

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Income Tax Reconciliation, Tax Exempt Income, Interest

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

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-Name Accounting Standards Codification

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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 deductions. Including, but not limited to, extraterritorial income exclusion deduction, qualified production activity deduction, dividend deduction, deduction for dividend paid to employee stock ownership plan, Medicare prescription drug benefit subsidy deduction, and other deductions.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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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 tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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