Acquisitions - Acquisition of Major Energy Companies (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill	$ 80,947	$ 79,147
National Gas & Electric, LLC \| Major Energy Companies
Business Acquisition [Line Items]
Cash	17,368	17,368
Property and equipment	14	14
Intangible assets - customer relationships & non-compete agreements	24,271	24,271
Other assets - trademarks	4,973	4,973
Non-current deferred tax assets	1,042	1,042
Goodwill	34,988	34,728
Net working capital, net of cash acquired	(6,746)	(6,746)
Fair value of derivative liabilities	(7,260)	(7,260)
Total	68,650	$ 68,390
Q1 2017 Adjustments
Goodwill	260
Total	$ 260

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Goodwill

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Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Working Capital, Net of Cash Acquired

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This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to items of consideration transferred in connection with a business combination for which the initial accounting was incomplete.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount, after allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences and carryforwards acquired at the acquisition date, classified as noncurrent.

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The amount of financial liabilities assumed (as defined) which have been recognized as of the acquisition date.

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Amount of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit, acquired at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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