Noncontrolling Interests (Redeemable Preferred Units) (Narrative) (Details) $ / shares in Units, $ in Millions			12 Months Ended
	Jun. 25, 2015 USD ($) $ / shares shares	May. 12, 2014 $ / shares shares	Dec. 31, 2014 shares	Dec. 31, 2013 shares	May. 15, 2015 $ / shares	Feb. 17, 2015 $ / shares	Nov. 05, 2014 USD ($)	Oct. 16, 2014 shares	Jul. 03, 2014 USD ($)	May. 19, 2014 shares	Aug. 29, 2013 d shares
Series Two Preferred Units [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Units converted (in shares)			666,116	329,881
Series Two Preferred Units [Member] | Noncontrolling Interests [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Liquidation preference percentage		6.00%
Operating Units liquidation preference (in dollars per share) | $ / shares		$ 38.10
OP Units for each Preferred Unit (in shares)		1.312336
Units converted (in shares)		666,116		329,881
Series Two Preferred Units On Converted Basis		874,168		432,914
Preferred Units Liquidation Preference | $ / shares		$ 50.00
Series Four Preferred Units [Member] | Noncontrolling Interests [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Series Four Preferred Units Redeemed	12,667										861,400
Series Four Preferred Units Released from Escrow								27,773		319,687
Redemption of Series Four Preferred Units | $	$ 0.6						$ 1.4		$ 16.0
Distributions to Series Two and Four Preferred Units (in dollars per share) | $ / shares					$ 0.25	$ 0.25
Series Four Preferred Units Annual Dividend Payable Rate	2.00%
Preferred Units Liquidation Preference | $ / shares	$ 50.00
First opportunity to redeem Series Four Preferred Units (in days) | d											30
OP Units [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Units converted (in shares)			874,168	432,914