Noncontrolling Interest - Redeemable Noncontrolling Interest (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance at beginning of year	$ 458,543	$ 479,606
Capital contributions	13,127	55,377
Dividends paid	(11,556)	(3,852)
Net loss attributable to RNCI	(12,029)	(64,794)
Accumulated other comprehensive income attributable to RNCI	(116)	(240)
Change in redemption value of RNCI	(9,178)	(7,554)
Balance at end of year	$ 438,791	$ 458,543
Subsidiaries \| Trident
Redeemable Noncontrolling Interest [Line Items]
Ownership interest held by noncontrolling owners	39.30%	39.30%
Subsidiaries \| Dowling
Redeemable Noncontrolling Interest [Line Items]
Ownership interest held by noncontrolling owners	1.70%	1.70%

Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Redeemable Noncontrolling Interest

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- Definition

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
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- Definition

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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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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Value of accretion of temporary equity during the period due to unpaid dividends.

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Value of accretion of temporary equity to its redemption value during the period.

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Value of new stock classified as temporary equity issued during the period.

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