Cost of Contracts, net (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cost of Contracts, net
Cost of contracts	$ 26,599	$ 24,203
Accumulated amortization	(12,384)	(9,917)
Cost of contracts, net	14,215	14,286
Expected future amortization of cost of contracts
2013	2,472
2014	2,623
2015	2,157
2016	1,915
2017	1,774
2018 and Thereafter	3,274
Cost of contracts, net	14,215	14,286
Amortization expense, cost of contracts	3,142	2,275	1,907
Losses on cost of contracts	$ 0	$ 0	$ 62
Weighted average useful life (in years)	9 years 6 months	9 years 8 months 12 days	9 years 6 months

Represents the amount of gains (losses) on other deferred costs.

No definition available.

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- Definition

Represents the amount of amortization expense expected to be recognized after the fifth fiscal year following the latest fiscal year for other deferred costs.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of amortization expense expected to be recognized during the next fiscal year following the latest fiscal year for other deferred costs.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of amortization expense expected to be recognized during the fifth fiscal year following the latest fiscal year for other deferred costs.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of amortization expense expected to be recognized during the fourth fiscal year following the latest fiscal year for other deferred costs.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of amortization expense expected to be recognized during the third fiscal year following the latest fiscal year for other deferred costs.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for other deferred costs.

+ References

No definition available.

+ Details

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- Definition

Useful life of other deferred costs, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Accumulated amortization of other deferred costs capitalized at the end of the reporting period. Does not include deferred finance costs, deferred acquisition costs of insurance companies, or deferred leasing costs for real estate operations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

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- Definition

Amount of other deferred costs charged against earnings in the period.

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- Definition

Gross amount of other deferred costs capitalized at the end of the reporting period. Does not include deferred finance costs or deferred acquisition costs of insurance companies.

+ References

+ Details

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- Definition

Net amount of other deferred costs capitalized at the end of the reporting period. Does not include deferred finance costs or deferred acquisition costs of insurance companies.

+ References

+ Details

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