Employee Benefit Plans (Policies)	12 Months Ended
Dec. 31, 2018
Employee Benefit Plans [Abstract]
Postemployment Benefit Plans, Policy	The Company has a qualified, noncontributory, defined benefit pension plan (“the Plan”) covering substantially all of its employees at December 31, 2018. Benefits paid from the plan are based on age, years of service, compensation, social security benefits and are determined in accordance with defined formulas. The Company’s policy is to fund the Plan in accordance with Employee Retirement Income Security Act of 1974 standards. Assets of the Plan are invested in publicly traded stocks and mutual funds. Prior to January 1, 2000, the Plan was a traditional defined benefit plan based on final average compensation. On January 1, 2000, the Plan was converted to a cash balance plan with grandfathering provisions for existing participants. Effective March 1, 2013, the Plan was amended. Benefit accruals for participants who, as of January 1, 2000, elected to continue participating in the traditional defined benefit plan design were frozen as of March 1, 2013. In May 2013, the noncontributory, frozen, defined benefit pension plan assumed from Alliance in the acquisition was merged into the Plan. In addition to the Plan, the Company provides supplemental employee retirement plans to certain current and former executives. The Company also assumed supplemental retirement plans for certain former executives in the Alliance acquisition. The supplemental employee retirement plans and the Plan are collectively referred to herein as “Pension Benefits.” In addition, the Company provides certain health care benefits for retired employees. Benefits were accrued over the employees’ active service period. Only employees that were employed by the Company on or before January 1, 2000 are eligible to receive post-retirement health care benefits. The Plan is contributory for participating retirees, requiring participants to absorb certain deductibles and coinsurance amounts with contributions adjusted annually to reflect cost sharing provisions and benefit limitations called for in the Plan. Employees become eligible for these benefits if they reach normal retirement age while working for the Company. For eligible employees described above, the Company funds the cost of post-retirement health care as benefits are paid. The Company elected to recognize the transition obligation on a delayed basis over twenty years. In addition, the Company assumed post-retirement medical life insurance benefits for certain Alliance employees, retirees and their spouses, if applicable, in the Alliance acquisition. These post-retirement benefits are referred to herein as “Other Benefits.” Accounting standards require an employer to: (1) recognize the overfunded or underfunded status of defined benefit post-retirement plans, which is measured as the difference between plan assets at fair value and the benefit obligation, as an asset or liability in its balance sheet; (2) recognize changes in that funded status in the year in which the changes occur through comprehensive income; and (3) measure the defined benefit plan assets and obligations as of the date of its year-end balance sheet.

The Company has a qualified, noncontributory, defined benefit pension plan (“the Plan”) covering substantially all of its employees at December 31, 2018. Benefits paid from the plan are based on age, years of service, compensation, social security benefits and are determined in accordance with defined formulas. The Company’s policy is to fund the Plan in accordance with Employee Retirement Income Security Act of 1974 standards. Assets of the Plan are invested in publicly traded stocks and mutual funds. Prior to January 1, 2000, the Plan was a traditional defined benefit plan based on final average compensation. On January 1, 2000, the Plan was converted to a cash balance plan with grandfathering provisions for existing participants. Effective March 1, 2013, the Plan was amended. Benefit accruals for participants who, as of January 1, 2000, elected to continue participating in the traditional defined benefit plan design were frozen as of March 1, 2013. In May 2013, the noncontributory, frozen, defined benefit pension plan assumed from Alliance in the acquisition was merged into the Plan.

In addition to the Plan, the Company provides supplemental employee retirement plans to certain current and former executives. The Company also assumed supplemental retirement plans for certain former executives in the Alliance acquisition.

The supplemental employee retirement plans and the Plan are collectively referred to herein as “Pension Benefits.”

In addition, the Company provides certain health care benefits for retired employees. Benefits were accrued over the employees’ active service period. Only employees that were employed by the Company on or before January 1, 2000 are eligible to receive post-retirement health care benefits. The Plan is contributory for participating retirees, requiring participants to absorb certain deductibles and coinsurance amounts with contributions adjusted annually to reflect cost sharing provisions and benefit limitations called for in the Plan. Employees become eligible for these benefits if they reach normal retirement age while working for the Company. For eligible employees described above, the Company funds the cost of post-retirement health care as benefits are paid. The Company elected to recognize the transition obligation on a delayed basis over twenty years. In addition, the Company assumed post-retirement medical life insurance benefits for certain Alliance employees, retirees and their spouses, if applicable, in the Alliance acquisition. These post-retirement benefits are referred to herein as “Other Benefits.”

Accounting standards require an employer to: (1) recognize the overfunded or underfunded status of defined benefit post-retirement plans, which is measured as the difference between plan assets at fair value and the benefit obligation, as an asset or liability in its balance sheet; (2) recognize changes in that funded status in the year in which the changes occur through comprehensive income; and (3) measure the defined benefit plan assets and obligations as of the date of its year-end balance sheet.