Noncontrolling Interest, Percent Allowed To Be Purchased By Company Annually

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- Definition

Noncontrolling Interest, Percent Of Equity Interest Obligated To Retain

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- Definition

Noncontrolling Interest, Percent Of Equity Interests Available To Put Up Annually

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- Definition

Noncontrolling Interest, Percent Of Ownership Interests Allowed To Be Put Up In One Year

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- Definition

Noncontrolling Interest, Percent Of Total Equity Interests Available To Put Up Annually

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- Definition

Noncontrolling Interest, Period After Which Percent Of Equity Interests Available To Put Up Annually

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- Definition

Noncontrolling Interest, Vesting Period

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- Definition

Redeemable and Nonredeemable Noncontrolling Interest - Total of noncontrolling interests held in both temporary (redeemable) and permanent (nonredeemable) (mezzanine) equity.

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No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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- Definition

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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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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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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- Definition

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

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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Noncontrolling Interests Text Details (Details) - USD ($) $ in Thousands				3 Months Ended								12 Months Ended
	Jun. 01, 2006	Feb. 06, 2004	Feb. 05, 2004	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Noncontrolling Interest [Line Items]
Net income attributable to noncontrolling interests				$ 545	$ 924	$ 968	$ 1,050	$ 1,278	$ 1,074	$ 1,150	$ 966	$ 3,487	$ 4,468	$ 4,157
Redeemable noncontrolling interests				2,526				17,461				2,526	17,461
Noncontrolling interests				0				5,186				0	5,186
Percentage of voting interest acquired		80.00%
Redeemable and nonredeemable noncontrolling interest				2,526				22,647				2,526	22,647
Anchor
Noncontrolling Interest [Line Items]
Noncontrolling interests														2,900
Ownership percentage by noncontrolling owners	20.00%
Vesting period	5 years
Percent of equity interests available to put annually	10.00%
Period after which percent of equity interests available to put up annually	6 months
Percent of equity interest obligated to retain	50.00%
Redeemable and nonredeemable noncontrolling interest				$ 0				9,761				$ 0	9,761
BOS
Noncontrolling Interest [Line Items]
Noncontrolling interests														$ 2,300
Ownership percentage by noncontrolling owners			30.00%	30.00%								30.00%
Vesting period			7 years
Percent of equity interests available to put annually			10.00%
Percent of total equity interests available to put up annually			1.00%
Percent of equity interest obligated to retain			50.00%
Redeemable and nonredeemable noncontrolling interest				$ 0				8,057				$ 0	8,057
DGHM
Noncontrolling Interest [Line Items]
Ownership percentage by noncontrolling owners		20.00%
Vesting period		5 years
Percent of ownership interests allowed to be put up in one year		40.00%
Period after which percent of equity interests available to put up annually		6 months
Percent of equity interest obligated to retain		50.00%
Redeemable and nonredeemable noncontrolling interest				$ 2,526				$ 4,829				$ 2,526	$ 4,829
Anchor
Noncontrolling Interest [Line Items]
Percentage of voting interest acquired	80.00%
BOS
Noncontrolling Interest [Line Items]
Percentage of voting interest acquired			70.00%
Minimum \| DGHM
Noncontrolling Interest [Line Items]
Percent of equity interests available to put annually		10.00%
Percent allowed to be purchased by company annually		10.00%
Maximum \| DGHM
Noncontrolling Interest [Line Items]
Percent of equity interests available to put annually		20.00%
Percent allowed to be purchased by company annually		20.00%