Noncontrolling Interests Redeemable Noncontrolilng Interests Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 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 (Loss) Attributable to Noncontrolling Interest	$ 968	$ 1,150	2,018	$ 2,116
Redeemable noncontrolling interests at end of period	10,747		10,747
Nonredeemable Noncontrolling Interest at end of period	1,996		1,996
Redeemable Noncontrolling Interest [Member]
Redeemable Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests at beginning of period	16,322	17,232	17,461	16,972
Net Income (Loss) Attributable to Noncontrolling Interest	732	859	1,491	1,583
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(712)	(842)	(1,449)	(1,545)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	(6,520)	66	(6,353)	132
Amortization of Noncontrolling Interest Equity Compensation	126	102	248	204
Noncontrolling Interest, adjustment to fair value	799	(201)	(651)	(130)
Redeemable noncontrolling interests at end of period	10,747	17,216	10,747	17,216
Noncontrolling Interest [Member]
Redeemable Noncontrolling Interest [Line Items]
Nonredeemable Noncontrolling Interest at beginning of period	4,825	3,993	5,186	4,161
Net Income (Loss) Attributable to Noncontrolling Interest	236	291	527	533
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(227)	(284)	(509)	(519)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	(3,051)	0	(3,051)	0
Amortization of Noncontrolling Interest Equity Compensation	0	250	161	506
Noncontrolling Interest, adjustment to fair value	213	125	(318)	(306)
Nonredeemable Noncontrolling Interest at end of period	$ 1,996	$ 4,375	$ 1,996	$ 4,375

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).

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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.

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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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