11) Retirement Plans: Deferred Compensation Plans (Details)	12 Months Ended
Dec. 31, 2017
DeferredCompensationPlanMember
Deferred Compensation Arrangements, Overall, Description	Under the terms of the Plan, the Company will provide deferred compensation for a select group of management or highly compensated employees, within the meaning of Sections 201(2), 301(a)(3) and 401(a)(1) of the Employee Retirement Income Security Act of 1974, as amended. The Board has appointed a Committee of the Company to be the Plan Administrator and to determine the employees who are eligible to participate in the plan. The employees who participate may elect to defer a portion of their compensation into the plan.

General description of deferred compensation arrangements. Deferred compensation represents currently earned compensation that, under the terms of a profit-sharing, rabbi trust, pension, employee contract, or equity-based (including stock or unit option) plan, is not actually paid until a later date and is therefore not taxable until that date. May also include some split-dollar life insurance arrangements. This type of arrangement is usually made to help employees postpone paying taxes on the income and also to retain employees longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

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