Equity-Based Compensation Plans (Schedule of Company's Stock Options Outstanding) (Details) - Stock Options [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Number of shares:
Balance options outstanding, beginning	117,408	179,102	392,658
Granted
Exercised	(23,710)	(7,353)	(4,500)
Forfeited			(75,000)
Expired	(33,750)	(54,341)	(134,056)
Balance options outstanding, end	59,948	117,408	179,102
Exercisable, end of period	59,948	117,408
Weighted Average Exercise Price
Balance, beginning	$ 18.12	$ 18.55	$ 17.71
Granted
Exercised	15.84	15.20	15.58
Forfeited			9.76
Expired	21.39	19.93	21.10
Outstanding	17.18	18.12	$ 18.55
Exercisable	$ 17.18	$ 18.12
Weighted- Average Contractual Term (years), outstanding	1 year 4 months 21 days
Weighted- Average Contractual Term (years), exercisable	1 year 4 months 21 days
Aggregate Intrinsic Value, exercised	$ 81,894	$ 19,843	$ 6,525
Aggregate Intrinsic Value, outstanding	597,148
Aggregate Intrinsic Value, exercisable	$ 597,148

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Information pertaining to the weighted average exercise price of stock based compensation awards.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Weighted average price of options that were either forfeited or expired.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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