Noncontrolling Interests Redeemable Noncontrolilng Interests Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Redeemable Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests at beginning of period	$ 17,461
Nonredeemable Noncontrolling Interest at beginning of period	5,186
Net income attributable to noncontrolling interests	1,050	$ 966
Redeemable noncontrolling interests at end of period	16,322
Nonredeemable Noncontrolling Interest at end of period	4,825
Redeemable Noncontrolling Interest [Member]
Redeemable Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests at beginning of period	17,461	16,972
Net income attributable to noncontrolling interests	758	724
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(736)	(703)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	167	66
Amortization of Noncontrolling Interest Equity Compensation	122	102
Noncontrolling Interest, adjustment to fair value	(1,450)	71
Redeemable noncontrolling interests at end of period	16,322	17,232
Noncontrolling Interest [Member]
Redeemable Noncontrolling Interest [Line Items]
Nonredeemable Noncontrolling Interest at beginning of period	5,186	4,161
Net income attributable to noncontrolling interests	291	242
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(282)	(235)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	0	0
Amortization of Noncontrolling Interest Equity Compensation	161	256
Noncontrolling Interest, adjustment to fair value	(531)	(431)
Nonredeemable Noncontrolling Interest at end of period	$ 4,825	$ 3,993

Amortization of Noncontrolling Interest Equity Compensation

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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.

+ References

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- Definition

Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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Net Increase or Decrease in balance of noncontrolling interest in the subsidiary during the reporting period.

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-Publisher FASB
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- Definition

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

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Portion of equity (net assets) in a subsidiary not attributable, directly or indirectly, to the parent entity which is not redeemable by the parent entity.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
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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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No definition available.

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