Equity - Stock Repurchase Authorization (Details) shares in Millions	12 Months Ended
Dec. 31, 2016 USD ($) shares
Equity
Authorized amount for share repurchase program	$ 100,000,000
Company repurchased, shares (in shares) \| shares	0.5
Repurchase of Company stock for retirement	$ 24,811,000

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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