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Equity-Based Compensation (Narrative) (Details) (USD $) | 12 Months Ended | 1 Months Ended | 12 Months Ended | 36 Months Ended |  | 12 Months Ended | 36 Months Ended | 12 Months Ended | 36 Months Ended | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2013 2005 Equity Incentive Plan [Member] | Jan. 31, 2013 Performance Stock Units [Member] | Jan. 31, 2012 Performance Stock Units [Member] | Dec. 31, 2013 Performance Stock Units [Member] | Dec. 31, 2012 Performance Stock Units [Member] | Dec. 31, 2011 Performance Stock Units [Member] | Sep. 30, 2009 Performance Stock Units [Member] | Dec. 31, 2013 Management Stock Purchase Plan [Member] | Dec. 31, 2012 Management Stock Purchase Plan [Member] | Dec. 31, 2011 Management Stock Purchase Plan [Member] | Dec. 31, 2013 Maximum [Member] Performance Stock Units [Member] | Dec. 31, 2011 Maximum [Member] Performance Stock Units [Member] | Dec. 31, 2013 Minimum [Member] Performance Stock Units [Member] | Dec. 31, 2011 Minimum [Member] Performance Stock Units [Member] | Dec. 31, 2013 Unvested Restricted Stock Units [Member] | Dec. 31, 2012 Unvested Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Typical vesting period, in years | 4 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum number of shares that may be issued under the Plan |  |  |  | 3,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum number of shares that may be issued in connection with grants of incentive stock options and rights |  |  |  | 900,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares available for issuance under the Plan | 605,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized portion of compensation expense related to awards |  |  | $ 885,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options granted | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of target performance stock units earned |  |  |  |  |  |  | 50.00% | 58.30% |  |  |  |  |  |  | 200.00% |  | 0.00% |  |
Performance stock unit conversion date fair value |  |  |  |  |  | 8,319,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Targeted Performance Stock Units |  |  |  |  |  |  | 246,000 | 280,000 | 868,000 |  |  |  |  |  |  |  |  |  |
Performance stock units outstanding |  |  |  |  |  |  | 246,000 | 280,000 | 868,000 | 905,000 |  |  |  |  |  |  |  |  |
Shares awarded |  |  |  |  | 304,000 | 295,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Performance stock unit grant-date fair value |  |  |  |  | 4,123,000 | 4,152,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Performance stock units earned |  |  |  |  |  |  | 123,000 | 163,200 | 684,299 |  |  |  |  |  |  |  |  |  |
Performance stock unit vesting period |  |  |  |  |  |  |  |  |  |  |  |  |  | 3 years |  | 1 year |  |  |
Service period |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |
Weighted average fair value of per unit awarded |  |  |  |  |  |  |  |  |  |  | $ 15.97 | $ 12.30 |  |  |  |  |  |  |
Number of restricted stock units credited to participant accounts | 614,888 | 777,159 |  |  |  |  |  |  |  |  | 132,037 | 253,587 | 164,589 |  |  |  |  | 47,268 | 71,992
Market price of common stock, per share | $ 18.59 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requisite vesting age | 60 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accrues interest |  |  |  |  |  |  |  |  |  |  | 2.00% |  |  |  |  |  |  |  |
Intrinsic value of options exercisable | 1,759,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average remaining life of options exercisable | 4 years 9 months 18 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized compensation cost | $ 3,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average cost recognition period, in years | 2 years 10 months 24 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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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 The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(2)(c) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph c(1) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(2)(c) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + 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 (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(2)(b) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(2)(a) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition Weighted average remaining contractual term for equity-based awards excluding options, 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 (e)(1) -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 Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: 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 The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Net number of share options (or share units) granted during 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 (c)(1)(iv)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(1)(d) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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