Noncontrolling Interests Text Details (Details) - USD ($) $ in Thousands		3 Months Ended																12 Months Ended
		Dec. 31, 2016		Sep. 30, 2016	[1]	Jun. 30, 2016	[1]	Mar. 31, 2016	[1]	Dec. 31, 2015		Sep. 30, 2015	[1]	Jun. 30, 2015	[1]	Mar. 31, 2015	[1]	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Noncontrolling Interest [Line Items]
Net Income (Loss) Attributable to Noncontrolling Interest		$ 1,147	[1]	$ 1,110		$ 989		$ 911		$ 921	[1]	$ 994		$ 1,263		$ 1,229		$ 4,157	$ 4,407	$ 4,750
Redeemable noncontrolling interests		16,972								18,088								16,972	18,088
Nonredeemable Noncontrolling Interest		4,161								3,393								4,161	3,393
Anchor [Member]
Noncontrolling Interest [Line Items]
Nonredeemable Noncontrolling Interest		2,000								1,300								2,000	1,300
Redeemable and Nonredeemable Noncontrolling Interest		10,934								11,907								10,934	11,907
BOS [Member]
Noncontrolling Interest [Line Items]
Nonredeemable Noncontrolling Interest		2,200								2,100								2,200	2,100
Redeemable and Nonredeemable Noncontrolling Interest		6,782								6,744								6,782	6,744
DGHM [Member]
Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests	[2]	$ 3,417								$ 2,830								$ 3,417	$ 2,830

[1] Due to rounding, the sum of the four quarters may not add to the year to date total.

[2] Only includes redeemable noncontrolling interests.