Share-Based Compensation (Summary of Stock Options Outstanding) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of shares vested and exercisable	499,419	587,427
Options vested and exercisable weighted average remaining contractual life	5 years 0 months 0 days	4 years 10 months 12 days
Options vested and exercisable weighted average exercise price	$ 6.73	$ 5.63
Options vested and exercisable intrinsic value	$ 8,892	$ 7,609
$4.31-$7.18
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range	$ 4.31
Range of exercise prices, upper range	$ 7.18
Number of shares vested and exercisable	331,944
Options vested and exercisable weighted average remaining contractual life	4 years 0 months 15 days
Options vested and exercisable weighted average exercise price	$ 5.71
Options vested and exercisable intrinsic value	6,246
$7.44-$8.17
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range	$ 7.44
Range of exercise prices, upper range	$ 8.17
Number of shares vested and exercisable	15,300
Options vested and exercisable weighted average remaining contractual life	6 years 2 months 10 days
Options vested and exercisable weighted average exercise price	$ 7.65
Options vested and exercisable intrinsic value	258
$8.65-$23.57
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range	$ 8.65
Range of exercise prices, upper range	$ 23.57
Number of shares vested and exercisable	152,175
Options vested and exercisable weighted average remaining contractual life	6 years 11 months 22 days
Options vested and exercisable weighted average exercise price	$ 8.84
Options vested and exercisable intrinsic value	2,388
$3.21-$6.89
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range		$ 3.21
Range of exercise prices, upper range		$ 6.89
Number of shares vested and exercisable		448,440
Options vested and exercisable weighted average remaining contractual life		3 years 11 months 18 days
Options vested and exercisable weighted average exercise price		$ 4.86
Options vested and exercisable intrinsic value		6,153
$7.13-$8.17
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range		$ 7.13
Range of exercise prices, upper range		$ 8.17
Number of shares vested and exercisable		56,175
Options vested and exercisable weighted average remaining contractual life		7 years 2 months 1 day
Options vested and exercisable weighted average exercise price		$ 7.25
Options vested and exercisable intrinsic value		637
$8.65-$19.13
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range		$ 8.65
Range of exercise prices, upper range		$ 19.13
Number of shares vested and exercisable		82,812
Options vested and exercisable weighted average remaining contractual life		8 years 1 month 25 days
Options vested and exercisable weighted average exercise price		$ 8.69
Options vested and exercisable intrinsic value		$ 819

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.

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

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Weighted average remaining contractual term of exercisable stock 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

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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