Shareholders' Equity Share-based Compensation (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based incentive plan, number of shares authorized for issuance	2,500,000
Share-based incentive plan, number of shares remaining for issuance	1,078,908
Total share-based compensation expense	$ 2,719,000	$ 2,354,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value	3,703,000	2,708,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Restricted stock outstanding as of beginning of the period	520,969	448,283
Restricted stock granted during the period	457,538	255,158
Restricted stock vested during the period	(246,698)	(182,472)
Restricted stock outstanding as of end of the period	731,809	520,969
Nonvested restricted stock, fair value remaining to be amortized	4,294,000
Restricted Stock [Member] \| Within twelve months [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Nonvested restricted stock, fair value remaining to be amortized	2,265,000
Restricted Stock [Member] \| One to two years [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Nonvested restricted stock, fair value remaining to be amortized	1,452,000
Restricted Stock [Member] \| Two to three years [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Nonvested restricted stock, fair value remaining to be amortized	541,000
Restricted Stock [Member] \| Three to four years [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Nonvested restricted stock, fair value remaining to be amortized	$ 36,000

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

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

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

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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)

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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

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-SubTopic 10

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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-Name Accounting Standards Codification

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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

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-Publisher FASB

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-Paragraph 2

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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

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- Definition

Aggregate value of stock related to Restricted Stock Awards issued during the period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

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-Number 210

-Section 02

-Paragraph 29, 30, 31

-Article 5

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