Stockholders' Equity	12 Months Ended
Dec. 31, 2017
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity On November 12, 2002, the Company’s Board of Directors amended the Company’s Articles of Incorporation, creating a series of Class A Junior Participating Preferred Stock (the “Class A Preferred Stock”). The Class A Preferred Stock is senior to common stock in dividends or distributions of assets upon liquidations, dissolutions or winding up of the Company. Dividends on the Class A Preferred Stock are cumulative and accrue from the quarterly dividend payment date. Each share of Class A Preferred Stock entitles the holder thereof to 100 votes on all matters submitted to a vote of shareholders of the Company. These shares were reserved for issuance under the Shareholder Rights Plan (the “Plan”), which was adopted on November 21, 2002, by the Company’s Board of Directors. Under the terms of the Plan, the Company’s common stock acquired by a person or a group buying 15% or more of the Company’s common stock would be diluted, except in transactions approved by the Board of Directors. In connection with the Plan, the Company’s Board of Directors declared a dividend distribution of one right (a “Right”) for each outstanding share of the Company’s common stock paid on December 16, 2002, to shareholders of record at the close of business on December 2, 2002. Each Right entitles the registered holder to purchase from the Company a unit (a “Unit”) consisting of one one-hundredth of a share of Class A Preferred Stock. Under the Plan, the Rights detach and become exercisable upon the earlier of (a) ten (10) days following public announcement that a person or group of affiliated or associated persons has acquired, or obtained the right to acquire, beneficial ownership of 15% or more of the outstanding shares of the Company’s common stock, or (b) ten (10) business days following the commencement of, or first public announcement of the intent of a person or group to commence, a tender offer or exchange offer that would result in a person or group beneficially owning 15% or more of such outstanding shares of the Company’s common stock. The exercise price, the kind and the number of shares covered by each right are subject to adjustment upon the occurrence of certain events described in the Plan. If any person or group of affiliated or associated persons acquires beneficial ownership of 15% or more of the outstanding common stock, each holder of a Right (other than the acquiring person or group) will have the right to buy, at the exercise price, common stock of the Company having a market value of twice the exercise price. If the Company is acquired in a merger or consolidation in which the Company is not the surviving corporation, or the Company engages in a merger or consolidation in which the Company is the surviving corporation and the Company’s common stock is changed or exchanged, or more than 50% of the Company’s assets or earning power is sold or transferred, the Rights entitle a holder (other than the acquiring person or group) to buy, at the exercise price, stock of the acquiring company having a market value equal to twice the exercise price. At any time after a person or group of affiliated or associated persons has acquired beneficial ownership of 15% or more of the outstanding common stock and prior to the acquisition by such person or group of 50% or more of the outstanding common stock, the Company’s Board of Directors may exchange the Rights (other than the Rights owned by such person or group), in whole or in part, at an exchange ratio of one share of the Company’s common stock, or one one-hundredth of a share of Preferred Stock, per Right. The Rights are redeemable upon action by the Board of Directors at a price of $0.01 per right at any time before they become exercisable. Until the Rights become exercisable, they are evidenced only by the common stock certificates and are transferred with and only with such certificates. On October 31, 2012, the Plan was amended to, among other things, extend the expiration date of the plan from November 11, 2012 to October 31, 2022 and increase the exercise price of the stock purchase rights from $80 per unit to $220 per unit. In connection with the amendments to the shareholders’ rights plan, the Board of Directors of the Company also amended the Company’s Articles of Incorporation to increase the number of shares designated under the rights plan as Series A Participating Preferred Stock from 100,000 shares to 200,000 shares. There were 1,000,000 shares of Preferred Stock authorized as of December 31, 2017 and 2016, with 200,000, being designated Class A Junior Participating Preferred Stock.

Stockholders’ Equity

On November 12, 2002, the Company’s Board of Directors amended the Company’s Articles of Incorporation, creating a series of Class A Junior Participating Preferred Stock (the “Class A Preferred Stock”). The Class A Preferred Stock is senior to common stock in dividends or distributions of assets upon liquidations, dissolutions or winding up of the Company. Dividends on the Class A Preferred Stock are cumulative and accrue from the quarterly dividend payment date. Each share of Class A Preferred Stock entitles the holder thereof to 100 votes on all matters submitted to a vote of shareholders of the Company. These shares were reserved for issuance under the Shareholder Rights Plan (the “Plan”), which was adopted on November 21, 2002, by the Company’s Board of Directors. Under the terms of the Plan, the Company’s common stock acquired by a person or a group buying 15% or more of the Company’s common stock would be diluted, except in transactions approved by the Board of Directors.

In connection with the Plan, the Company’s Board of Directors declared a dividend distribution of one right (a “Right”) for each outstanding share of the Company’s common stock paid on December 16, 2002, to shareholders of record at the close of business on December 2, 2002. Each Right entitles the registered holder to purchase from the Company a unit (a “Unit”) consisting of one one-hundredth of a share of Class A Preferred Stock. Under the Plan, the Rights detach and become exercisable upon the earlier of (a) ten (10) days following public announcement that a person or group of affiliated or associated persons has acquired, or obtained the right to acquire, beneficial ownership of 15% or more of the outstanding shares of the Company’s common stock, or (b) ten (10) business days following the commencement of, or first public announcement of the intent of a person or group to commence, a tender offer or exchange offer that would result in a person or group beneficially owning 15% or more of such outstanding shares of the Company’s common stock. The exercise price, the kind and the number of shares covered by each right are subject to adjustment upon the occurrence of certain events described in the Plan.

If any person or group of affiliated or associated persons acquires beneficial ownership of 15% or more of the outstanding common stock, each holder of a Right (other than the acquiring person or group) will have the right to buy, at the exercise price, common stock of the Company having a market value of twice the exercise price. If the Company is acquired in a merger or consolidation in which the Company is not the surviving corporation, or the Company engages in a merger or consolidation in which the Company is the surviving corporation and the Company’s common stock is changed or exchanged, or more than 50% of the Company’s assets or earning power is sold or transferred, the Rights entitle a holder (other than the acquiring person or group) to buy, at the exercise price, stock of the acquiring company having a market value equal to twice the exercise price. At any time after a person or group of affiliated or associated persons has acquired beneficial ownership of 15% or more of the outstanding common stock and prior to the acquisition by such person or group of 50% or more of the outstanding common stock, the Company’s Board of Directors may exchange the Rights (other than the Rights owned by such person or group), in whole or in part, at an exchange ratio of one share of the Company’s common stock, or one one-hundredth of a share of Preferred Stock, per Right.

The Rights are redeemable upon action by the Board of Directors at a price of $0.01 per right at any time before they become exercisable. Until the Rights become exercisable, they are evidenced only by the common stock certificates and are transferred with and only with such certificates.

On October 31, 2012, the Plan was amended to, among other things, extend the expiration date of the plan from November 11, 2012 to October 31, 2022 and increase the exercise price of the stock purchase rights from $80 per unit to $220 per unit. In connection with the amendments to the shareholders’ rights plan, the Board of Directors of the Company also amended the Company’s Articles of Incorporation to increase the number of shares designated under the rights plan as Series A Participating Preferred Stock from 100,000 shares to 200,000 shares. There were 1,000,000 shares of Preferred Stock authorized as of December 31, 2017 and 2016, with 200,000, being designated Class A Junior Participating Preferred Stock.