Share-Based Compensation (Details Textuals)	12 Months Ended
Dec. 31, 2015 USD ($) years $ / shares shares	Dec. 31, 2014 USD ($) shares	Dec. 31, 2013 USD ($) shares
Share-Based Compensation Textuals [Abstract]
Number of Shares Authorized \| shares	1,200,000
Unrecognized compensation cost related to nonvested awards net of tax Total	$ 17,200,000
Unrecognized compensation cost period for recognition, years	3 years
Unrecognized compensation cost period for recognition, weighted-average, years \| years	0.7
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Total intrinsic value of options exercised		$ 400,000	$ 900,000
Maximum employee Contribution to employee stock purchase plans based on compensation, percentage	15.00%
Maximum employee Contribution to employee stock purchase plans based on compensation, amount	$ 25,000
Common stock discount under employee stock purchase plans	15.00%
Employee Stock Purchase Plans,Fair value estimation	estimated by adding the fair value of 0.15 of one share of stock to the fair value of 0.85 of an option on one share of stock
Stock Issued During Period, Shares, Employee Stock Purchase Plans \| shares	100,000	100,000	100,000
Employee Stock [Member]
Share-Based Compensation Textuals [Abstract]
Number of Shares Authorized \| shares	100,000
Deferred Stock Units [Member]
Share-Based Compensation Textuals [Abstract]
Vesting period of performance units	1 year
Restricted Stock Awards [Member]
Share-Based Compensation Textuals [Abstract]
Vesting period of performance units	3 years
Restricted Stock [Member]
Share-Based Compensation Textuals [Abstract]
Total fair value of restricted stock awards granted	$ 26,000,000	$ 25,500,000	$ 29,200,000
Total fair value of restricted stock awards vested	$ 35,700,000	24,500,000	13,200,000
Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Textuals [Abstract]
Vesting period of performance units	5 years
Total fair value of restricted stock awards granted	$ 5,500,000	4,200,000	7,600,000
Total fair value of restricted stock awards vested	$ 2,100,000	$ 100,000	$ 100,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	1.70%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	48.10%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	1.60%
Vesting Period [Domain]
Share-Based Compensation Textuals [Abstract]
Vesting period of performance units	3 years
Cliff Vest [Domain]
Share-Based Compensation Textuals [Abstract]
Vesting period of performance units	3 years
Performance unit [Member]
Share-Based Compensation Textuals [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Description	three
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	1.10%	0.80%	0.40%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	45.00%	45.30%	47.30%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	2.40%	1.70%	1.40%
Number of outstanding units vested \| shares	17,525
Aggregate intrinsic value	$ 100,000
Conversion price per share \| $ / shares	$ 8.50

Common stock discount under employee stock purchase plans.

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Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition, Weighted-Average

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- Definition

Employee Stock Purchase Plans,Fair value estimation.

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Maximum employee Contribution to employee stock purchase plans based on compensation, Amount.

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Maximum employee Contribution to employee stock purchase plans based on compensation,Pecentage.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options granted in period fair value.

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Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Fair Value.

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- Definition

Share-based Compensation Arrangement, by Share-based Payment Award Options, Conversion Price Per Share.

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- Definition

Share-Based Compensation.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

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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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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- Definition

As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

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