Noncontrolling Interests Redeemable Noncontrolling Interests Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended																12 Months Ended
	Dec. 31, 2016		Sep. 30, 2016	[1]	Jun. 30, 2016	[1]	Mar. 31, 2016		Dec. 31, 2015		Sep. 30, 2015	[1]	Jun. 30, 2015	[1]	Mar. 31, 2015		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Redeemable Noncontrolling Interest [Line Items]
Redeemable Noncontrolling Interests, Equity, Carrying Amount, Beginning of Period							$ 18,088										$ 18,088
Nonredeemable Noncontrolling Interest, Beginning of Period							3,393										3,393
Net Income (Loss) Attributable to Noncontrolling Interest	$ 1,147	[1]	$ 1,110		$ 989		911	[1]	$ 921	[1]	$ 994		$ 1,263		$ 1,229	[1]	4,157	$ 4,407	$ 4,750
Redeemable Noncontrolling Interests, Equity, Carrying Amount, End of Period	16,972								18,088								16,972	18,088
Nonredeemable Noncontrolling Interest, End of Period	4,161								3,393								4,161	3,393
Anchor [Member]
Redeemable Noncontrolling Interest [Line Items]
Nonredeemable Noncontrolling Interest, Beginning of Period							1,300										1,300
Nonredeemable Noncontrolling Interest, End of Period	2,000								1,300								2,000	1,300
Redeemable Noncontrolling Interest [Member]
Redeemable Noncontrolling Interest [Line Items]
Redeemable Noncontrolling Interests, Equity, Carrying Amount, Beginning of Period							18,088								20,905		18,088	20,905	19,468
Net Income (Loss) Attributable to Noncontrolling Interest																	3,204	3,575	4,564
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders																	(3,112)	(4,189)	(4,426)
Redeemable Noncontrolling Interest Increase, Purchase or Sale of Additional Ownership Interest																	(765)	(1,666)	(1,879)
Noncontrolling Interest, Increase from Subsidiary Equity Issuance																	0	(1,652)	0
Amortization of Noncontrolling Interest Equity Compensation																	449	0	0
Noncontrolling Interest, Period Increase (Decrease)																	(892)	1,115	3,178
Redeemable Noncontrolling Interests, Equity, Carrying Amount, End of Period	16,972								18,088								16,972	18,088	20,905
Noncontrolling Interest [Member]
Redeemable Noncontrolling Interest [Line Items]
Nonredeemable Noncontrolling Interest, Beginning of Period							$ 3,393								$ 386		3,393	386	171
Net Income (Loss) Attributable to Noncontrolling Interest																	953	832	186
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders																	(942)	(422)	(177)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests																	(134)	419	74
Noncontrolling Interest, Increase from Subsidiary Equity Issuance																	0	1,652	0
Amortization of Noncontrolling Interest Equity Compensation																	747	472	96
Noncontrolling Interest, Period Increase (Decrease)																	144	54	36
Nonredeemable Noncontrolling Interest, End of Period	$ 4,161								$ 3,393								$ 4,161	$ 3,393	$ 386

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