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Share-Based Compensation (Details Textuals) | 12 Months Ended
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Dec. 31, 2016 USD ($) years shares | Dec. 31, 2015 USD ($) shares | Dec. 31, 2014 USD ($) shares
Share-Based Compensation Textuals [Abstract] |  |  |
Number of Shares Authorized | shares | 100,000 | 1,200,000 |
Unrecognized compensation cost related to nonvested awards net of tax Total | $ 4,900,000 |  |
Unrecognized compensation cost period for recognition, years | 1 year |  |
Unrecognized compensation cost period for recognition, weighted-average, years | years | 0.5 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period | 10 years |  |
Total intrinsic value of options exercised | $ 0 | $ 0 | $ 400,000
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
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 | $ 100,000 | $ 26,000,000 | $ 25,500,000
Total fair value of restricted stock awards vested | $ 21,300,000 | 35,700,000 | 24,500,000
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 | $ 2,700,000 | 5,500,000 | 4,200,000
Total fair value of restricted stock awards vested | $ 3,500,000 | $ 2,100,000 | $ 100,000
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%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate |  | 45.00% | 45.30%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate |  | 2.40% | 1.70%
Number of outstanding units vested | shares | 24,474 |  |

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- Definition Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition, Weighted-Average + References No definition available. + Details
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- Definition Employee Stock Purchase Plans,Fair value estimation. + References No definition available. + Details
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- Definition Maximum employee Contribution to employee stock purchase plans based on compensation, Amount. + References No definition available. + Details
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- Definition Share based compensation arrangement by share based payment award equity instruments other than options granted in period fair value. + References No definition available. + Details
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- Definition Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Fair Value. + References No definition available. + Details
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- Definition Unrecognized cost of unvested share-based compensation awards. + 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 (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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. + 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 (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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. + 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)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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 + Details
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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. + 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 (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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. + 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 (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + 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 (f)(2)(iv) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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). + 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)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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. + 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 (e)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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. + 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)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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 + Details
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