Equity Compensation (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Equity Compensation [Abstract]
Maximum shares of common stock	20,000,000
Maximum annual shares awarded to employee	500,000
Shares available for granting additional awards	7,409,690
Unrecognized compensation cost of non-vested equity compensation awards	$ 9,900
Unrecognized compensation cost of non-vested equity compensation awards expected to be recognized over a weighted average period (years)	2 years 6 months
Number of options granted	0	0
Intrinsic value of stock options exercised	$ 31	$ 600
Stock Options \| Minimum
Equity Compensation [Abstract]
Vesting period (months)	24 months
Stock Options \| Maximum
Equity Compensation [Abstract]
Vesting period (months)	72 months
Restricted Stock
Equity Compensation [Abstract]
Number of shares granted	0	0
Fair value of awards vested	$ 0	$ 0
Restricted Stock \| Minimum
Equity Compensation [Abstract]
Vesting period (months)	12 months
Restricted Stock \| Maximum
Equity Compensation [Abstract]
Vesting period (months)	84 months
Performance Shares
Equity Compensation [Abstract]
Number of shares granted	110,000	202,000
Fair value of awards vested	$ 1,600	$ 1,100
Number of performance awards earned	165,500
Performance Shares \| Minimum
Equity Compensation [Abstract]
Vesting period (months)	12 months
Performance awards, percentage range of target to be earned	0.00%	0.00%
Performance Shares \| Maximum
Equity Compensation [Abstract]
Vesting period (months)	60 months
Performance awards, percentage range of target to be earned	123.00%	132.00%
Stock Options
Equity Compensation [Abstract]
Maximum period for exercisable options (years and days)	10 years 1 day

Unrecognized cost of unvested share-based compensation awards.

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

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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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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
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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

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Net number of share options (or share units) granted during the period.

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

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Performance Awards, percentage range of target to be earned.

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The number of performance awards that were earned during the reporting period based on the level of attainment of specified performance objectives.

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The period of time, measured from grant date, before which an equity-based award expires as specified in the award agreement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The maximum number of shares that can be awarded per participant per year under an employee share-based payment plan.

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