Equity - Non-controlling Interests (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Variable Interest Entity [Line Items]
Net income attributable to non-controlling interests	$ 547	$ 997
Carrying value of the investments held by Quanta in variable interest entities	9,600		$ 9,600
Carrying amount of investments held by non-controlling interests in VIEs	1,313		1,294
Distributions to non-controlling interests	528	980
Discharges of notes receivable		$ 500
VIE
Variable Interest Entity [Line Items]
Carrying amount of investments held by non-controlling interests in VIEs	$ 1,300		$ 1,300

The increase (decrease) during the reporting period of the amounts due from borrowers for outstanding secured or unsecured loans evidenced by a note.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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The net carrying amount of the consolidated Variable Interest Entity's assets and liabilities included in the reporting entity's statement of financial position.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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