Recently Issued Accounting Standards - Contract Balances (Details) $ in Thousands	6 Months Ended
Jun. 30, 2018 USD ($)
Contract Assets [Roll Forward]
Balance, January 1, 2018	$ 14,611
Balance, June 30, 2018	17,908
Increase (decrease) in accounts receivable	3,297
Contract Liabilities, Current [Roll Forward]
Balance, January 1, 2018	860
Balance, June 30, 2018	685
Increase (decrease) in contract liability (current)	(175)
Contract Liabilities, Noncurrent [Roll Forward]
Balance, January 1, 2018	1,766
Balance, June 30, 2018	1,356
Increase (decrease) in contract liability (long-term)	$ (410)

Change in Contract with Customer, Asset [Roll Forward]

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- Definition

Change in Contract with Customer, Current Liability [Roll Forward]

+ References

No definition available.

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- Definition

Change in Contract with Customer, Noncurrent Liability [Roll Forward]

+ References

No definition available.

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- Definition

Increase (Decrease) In Contract With Customer, Asset, Current

+ References

No definition available.

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- Definition

Increase (Decrease) In Contract With Customer, Liability, Current

+ References

No definition available.

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- Definition

Increase (Decrease) In Contract With Customer, Liability, Noncurrent

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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