Stock-Based Compensation (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights			The Corporation maintains two stock-based compensation plans from which new grants could be issued. The Corporation's stock-based compensation plans permit Parent Corporation common stock to be issued to key employees and directors of the Corporation and its subsidiaries. The options granted under the plans are intended to be either incentive stock options or non-qualified options. Under the 2009 Equity Incentive Plan, a total of 363,081 shares are available for grant and issuance as of June 30, 2014. Under the 2003 Non-Employee Director Stock Option Plan, a total of 380,644 shares remain available for grant and issuance under the plan as of June 30, 2014. Such shares may be treasury shares, newly issued shares or a combination thereof.Options have been granted to purchase common stock principally at the fair market value of the stock at the date of grant. Options are exercisable over a three-year vesting period starting one year after the date of grant and generally expire ten years from the date of grant.Stock-based compensation expense for share-based payment awards is based on the grant date fair value estimated on the date of grant. The Corporation recognizes compensation costs for those shares expected to vest on a straight-line basis over the requisite service period of the award, which is generally the option vesting term of three years. The Corporation estimates the forfeiture rate based on its historical experience during the preceding seven fiscal years.
Share Based Compensation Arrangement by Share Based Payment Award Number of Plans	2		2
Share Based Compensation Arrangement by Share Based Payment Award Options Exercisable Period Over Vesting Period			3 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Allocated Share-based Compensation Expense (in Dollars)			$ 34,000	$ 25,000
Allocated Share-based Compensation Expense, Net of Tax (in Dollars)			20,000	15,000
Stock Issued During Period, Shares, Restricted Stock Award, Gross				18,829
Common Stock Underlying Grant Options	0	0	31,257	31,257
Restricted Stock [Member]
Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			5 years
Stock Issued During Period, Shares, Restricted Stock Award, Gross			18,829	18,829
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares			0
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized (in Dollars)	194,000		194,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition			5 years
Employee Stock Option [Member]
Stock-Based Compensation (Details) [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized (in Dollars)	$ 117,000		$ 117,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition			2 years 6 months
Employee Director Stock Option Plan 2009 [Member]
Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	363,081		363,081
Non Employee Director Stock Option Plan 2003 Member
Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	380,644		380,644
Minimum [Member]
Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			30 days
Maximum [Member]
Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			5 years