Noncontrolling Interests Redeemable Noncontrolilng Interests Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Redeemable Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests at beginning of period			$ 16,972
Nonredeemable Noncontrolling Interest at beginning of period			4,161
Net income attributable to noncontrolling interests	$ 1,074	$ 1,110	3,190	$ 3,010
Redeemable noncontrolling interests at end of period	15,882		15,882
Nonredeemable Noncontrolling Interest at end of period	4,792		4,792
Redeemable Noncontrolling Interest [Member]
Redeemable Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests at beginning of period	17,216	15,843	16,972	18,088
Net income attributable to noncontrolling interests	802	821	2,385	2,308
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(869)	(809)	(2,414)	(2,213)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	103	0	235	(766)
Amortization of Noncontrolling Interest Equity Compensation	102	115	306	302
Noncontrolling Interest, adjustment to fair value	(1,472)	229	(1,602)	(1,520)
Redeemable noncontrolling interests at end of period	15,882	16,199	15,882	16,199
Noncontrolling Interest [Member]
Redeemable Noncontrolling Interest [Line Items]
Nonredeemable Noncontrolling Interest at beginning of period	4,375	3,379	4,161	3,393
Net income attributable to noncontrolling interests	272	289	805	702
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(264)	(252)	(783)	(692)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	85	0	85	(18)
Amortization of Noncontrolling Interest Equity Compensation	250	237	756	501
Noncontrolling Interest, adjustment to fair value	74	129	(232)	(104)
Nonredeemable Noncontrolling Interest at end of period	$ 4,792	$ 3,782	$ 4,792	$ 3,782

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.

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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
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Net Increase or Decrease in balance of noncontrolling interest in the subsidiary during the reporting period.

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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.

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No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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