Share-Based Compensation (Summary of Nonvested Share Activity) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Number of Non-vested Shares
December 31, 2014 (in shares)	1,465
Granted (in shares)	561
Vested (in shares)	(488)
Forfeited (in shares)	(22)
March 31, 2015 (in shares)	1,516
Weighted Average Grant Date Fair Value
December 31, 2014 (in dollars per share)	$ 6.17
Granted (in dollars per share)	$ 6.64	$ 8.24
Vested (in dollars per share)	$ 5.17
Forfeited (in dollars per share)	$ 6.51
March 31, 2015 (in dollars per share)	$ 6.66

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

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ 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)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

Number of non-vested options outstanding.

+ References

No definition available.

+ Details

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- Definition

Number of non-vested options forfeited.

+ References

No definition available.

+ Details

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- Definition

Weighted average grant-date fair value of non-vested options forfeited.

+ References

No definition available.

+ Details

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

+ References

No definition available.

+ Details

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- Definition

Number of options vested.

+ References

No definition available.

+ Details

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- Definition

Weighted average grant-date fair value of options vested.

+ References

No definition available.

+ Details

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