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CONSOLIDATED STATEMENT OF CHANGES IN CAPITAL OF ERP OPERATING LIMITED PARTNERSHIP - USD ($) $ in Thousands | Total | Series K Preferred Stock [Member] | ERPOP [Member] | ERPOP [Member] Series K Preferred Stock [Member] | ERPOP [Member] PREFERENCE UNITS | ERPOP [Member] PREFERENCE UNITS Series K Preferred Stock [Member] | ERPOP [Member] GENERAL PARTNER | ERPOP [Member] LIMITED PARTNERS | ERPOP [Member] ACCUMULATED OTHER COMPREHENSIVE (LOSS) | ERPOP [Member] NONCONTROLLING INTERESTS – PARTIALLY OWNED PROPERTIES
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Balance, beginning of year at Dec. 31, 2012 |  |  |  |  | $ 50,000 |  | $ 7,432,961 | $ 159,606 | $ (193,148) | $ 77,688
Preference Units |  |  |  |  |  |  |  |  |  |
Partial redemption of 8.29% Series K Cumulative Redeemable |  |  |  |  | 0 |  |  |  |  |
Preferred Stock Preference Units Dividend Rate Percentage |  | 8.29% |  |  |  | 8.29% |  |  |  |
OP Unit Issuance: |  |  |  |  |  |  |  |  |  |
Conversion of OP Units held by Limited Partners into OP Units held by General Partner |  |  |  |  |  |  | 1,699 | (1,699) |  |
Issuance of OP Units |  |  |  |  |  |  | 1,929,868 |  |  |
Exercise of EQR share options |  |  |  |  |  |  | 17,252 |  |  |
EQR's Employee Share Purchase Plan (ESPP) |  |  |  |  |  |  | 3,401 |  |  |
Conversion of EQR restricted shares to restricted units |  |  |  |  |  |  | 0 | 0 |  |
Share-based employee compensation expense: |  |  |  |  |  |  |  |  |  |
EQR restricted shares |  |  |  |  |  |  | 13,264 |  |  |
EQR share options |  |  |  |  |  |  | 10,514 |  |  |
EQR ESPP discount |  |  |  |  |  |  | 632 |  |  |
OP Units repurchased and retired |  |  |  |  |  |  | 0 |  |  |
Net income available to Units – General Partner |  |  | $ 1,826,468 |  |  |  | 1,826,468 |  |  |
OP Units – General Partner distributions |  |  |  |  |  |  | (666,565) |  |  |
Offering costs |  |  |  |  |  |  | (1,047) |  |  |
Supplemental Executive Retirement Plan (SERP) |  |  |  |  |  |  | (422) |  |  |
Acquisition of Noncontrolling Interests – Partially Owned Properties |  |  |  |  |  |  | 0 |  |  | 0
Change in market value of Redeemable Limited Partners |  |  |  |  |  |  | 79,667 |  |  |
Adjustment for Limited Partners ownership in Operating Partnership |  |  |  |  |  |  | (35,329) | 35,329 |  |
LIMITED PARTNERS |  |  |  |  |  |  |  |  |  |
Issuance of restricted units to Limited Partners |  |  |  |  |  |  |  | 5 |  |
Conversion of OP Units held by Limited Partners into OP Units held by General Partner |  |  |  |  |  |  | 1,699 | (1,699) |  |
Conversion of restricted shares to restricted units |  |  |  |  |  |  | 0 | 0 |  |
Equity compensation associated with Units – Limited Partners |  |  |  |  |  |  |  | 13,609 |  |
Net income available to Units – Limited Partners |  |  | 75,278 |  |  |  |  | 75,278 |  |
Units – Limited Partners distributions |  |  |  |  |  |  |  | (26,277) |  |
Change in carrying value of Redeemable Limited Partners |  |  |  |  |  |  |  | (44,439) |  |
Adjustment for Limited Partners ownership in Operating Partnership |  |  |  |  |  |  | (35,329) | 35,329 |  |
Accumulated other comprehensive income (loss) – derivative instruments: |  |  |  |  |  |  |  |  |  |
Unrealized holding gains (losses) arising during the year | $ 18,771 |  | 18,771 |  |  |  |  |  | 18,771 |
Losses reclassified into earnings from other comprehensive income | (20,141) |  | (20,141) |  |  |  |  |  | 20,141 |
Accumulated other comprehensive income (loss) – other instruments: |  |  |  |  |  |  |  |  |  |
Unrealized holding gains arising during the year | 583 |  | 583 |  |  |  |  |  | 583 |
(Gains) on Sale of Securities, Net |  |  |  |  |  |  |  |  | (2,122) |
Currency translation adjustments arising during the year | 613 |  | 613 |  |  |  |  |  | 613 |
PARTIALLY OWNED PROPERTIES |  |  |  |  |  |  |  |  |  |
Net income (loss) attributable to Noncontrolling Interests | 1,905,353 |  | 1,905,353 |  |  |  |  |  |  | (538)
Contributions by Noncontrolling Interests | 27,660 |  | 27,660 |  |  |  |  |  |  | 27,660
Distributions to Noncontrolling Interests |  |  |  |  |  |  |  |  |  | (6,490)
Acquisition of Archstone |  |  |  |  |  |  |  |  |  | 28,263
Acquisition of Noncontrolling Interests – Partially Owned Properties |  |  |  |  |  |  | 0 |  |  | 0
Deconsolidation of previously consolidated Noncontrolling Interests |  |  |  |  |  |  |  |  |  | 0
Other |  |  |  |  |  |  |  |  |  | 0
Balance, end of period at Dec. 31, 2013 |  |  |  |  | 50,000 |  | 10,612,363 | 211,412 | (155,162) | 126,583
Preference Units |  |  |  |  |  |  |  |  |  |
Partial redemption of 8.29% Series K Cumulative Redeemable |  |  |  |  | 0 |  |  |  |  |
Preferred Stock Preference Units Dividend Rate Percentage |  | 8.29% |  | 8.29% |  | 0.00% |  |  |  |
OP Unit Issuance: |  |  |  |  |  |  |  |  |  |
Conversion of OP Units held by Limited Partners into OP Units held by General Partner |  |  |  |  |  |  | 2,365 | (2,365) |  |
Issuance of OP Units |  |  |  |  |  |  | 0 |  |  |
Exercise of EQR share options |  |  |  |  |  |  | 82,573 |  |  |
EQR's Employee Share Purchase Plan (ESPP) |  |  |  |  |  |  | 3,392 |  |  |
Conversion of EQR restricted shares to restricted units |  |  |  |  |  |  | 0 | 0 |  |
Share-based employee compensation expense: |  |  |  |  |  |  |  |  |  |
EQR restricted shares |  |  |  |  |  |  | 9,904 |  |  |
EQR share options |  |  |  |  |  |  | 7,349 |  |  |
EQR ESPP discount |  |  |  |  |  |  | 859 |  |  |
OP Units repurchased and retired |  |  |  |  |  |  | (1,777) |  |  |
Net income available to Units – General Partner |  |  | 627,163 |  |  |  | 627,163 |  |  |
OP Units – General Partner distributions |  |  |  |  |  |  | (723,782) |  |  |
Offering costs |  |  |  |  |  |  | (41) |  |  |
Supplemental Executive Retirement Plan (SERP) |  |  |  |  |  |  | 7,374 |  |  |
Acquisition of Noncontrolling Interests – Partially Owned Properties |  |  |  |  |  |  | (2,308) |  |  | (2,244)
Change in market value of Redeemable Limited Partners |  |  |  |  |  |  | (139,818) |  |  |
Adjustment for Limited Partners ownership in Operating Partnership |  |  |  |  |  |  | 4,992 | (4,992) |  |
LIMITED PARTNERS |  |  |  |  |  |  |  |  |  |
Issuance of restricted units to Limited Partners |  |  |  |  |  |  |  | 3 |  |
Conversion of OP Units held by Limited Partners into OP Units held by General Partner |  |  |  |  |  |  | 2,365 | (2,365) |  |
Conversion of restricted shares to restricted units |  |  |  |  |  |  | 0 | 0 |  |
Equity compensation associated with Units – Limited Partners |  |  |  |  |  |  |  | 11,969 |  |
Net income available to Units – Limited Partners |  |  | 24,831 |  |  |  |  | 24,831 |  |
Units – Limited Partners distributions |  |  |  |  |  |  |  | (28,676) |  |
Change in carrying value of Redeemable Limited Partners |  |  |  |  |  |  |  | 2,229 |  |
Adjustment for Limited Partners ownership in Operating Partnership |  |  |  |  |  |  | 4,992 | (4,992) |  |
Accumulated other comprehensive income (loss) – derivative instruments: |  |  |  |  |  |  |  |  |  |
Unrealized holding gains (losses) arising during the year | (33,306) |  | (33,306) |  |  |  |  |  | (33,306) |
Losses reclassified into earnings from other comprehensive income | (16,868) |  | (16,868) |  |  |  |  |  | 16,868 |
Accumulated other comprehensive income (loss) – other instruments: |  |  |  |  |  |  |  |  |  |
Unrealized holding gains arising during the year | 0 |  | 0 |  |  |  |  |  | 0 |
(Gains) on Sale of Securities, Net |  |  |  |  |  |  |  |  | 0 |
Currency translation adjustments arising during the year | (552) |  | (552) |  |  |  |  |  | (552) |
PARTIALLY OWNED PROPERTIES |  |  |  |  |  |  |  |  |  |
Net income (loss) attributable to Noncontrolling Interests | 658,683 |  | 658,683 |  |  |  |  |  |  | 2,544
Contributions by Noncontrolling Interests | 5,684 |  | 5,684 |  |  |  |  |  |  | 5,684
Distributions to Noncontrolling Interests |  |  |  |  |  |  |  |  |  | (7,827)
Acquisition of Archstone |  |  |  |  |  |  |  |  |  | 0
Acquisition of Noncontrolling Interests – Partially Owned Properties |  |  |  |  |  |  | (2,308) |  |  | (2,244)
Deconsolidation of previously consolidated Noncontrolling Interests |  |  |  |  |  |  |  |  |  | 0
Other |  |  |  |  |  |  |  |  |  | 169
Balance, end of period at Dec. 31, 2014 |  |  |  |  | 50,000 |  | 10,490,608 | 214,411 | (172,152) | 124,909
Preference Units |  |  |  |  |  |  |  |  |  |
Partial redemption of 8.29% Series K Cumulative Redeemable |  |  |  |  | (12,720) |  |  |  |  |
Preferred Stock Preference Units Dividend Rate Percentage |  | 8.29% |  | 8.29% |  | 8.29% |  |  |  |
OP Unit Issuance: |  |  |  |  |  |  |  |  |  |
Conversion of OP Units held by Limited Partners into OP Units held by General Partner |  |  |  |  |  |  | 4,966 | (4,966) |  |
Issuance of OP Units |  |  |  |  |  |  | 0 |  |  |
Exercise of EQR share options |  |  |  |  |  |  | 59,508 |  |  |
EQR's Employee Share Purchase Plan (ESPP) |  |  |  |  |  |  | 4,404 |  |  |
Conversion of EQR restricted shares to restricted units |  |  |  |  |  |  | (70) | 70 |  |
Share-based employee compensation expense: |  |  |  |  |  |  |  |  |  |
EQR restricted shares |  |  |  |  |  |  | 15,066 |  |  |
EQR share options |  |  |  |  |  |  | 3,756 |  |  |
EQR ESPP discount |  |  |  |  |  |  | 884 |  |  |
OP Units repurchased and retired |  |  |  |  |  |  | 0 |  |  |
Net income available to Units – General Partner |  |  | 863,277 |  |  |  | 863,277 |  |  |
OP Units – General Partner distributions |  |  |  |  |  |  | (804,825) |  |  |
Offering costs |  |  |  |  |  |  | (79) |  |  |
Supplemental Executive Retirement Plan (SERP) |  |  |  |  |  |  | 1,380 |  |  |
Acquisition of Noncontrolling Interests – Partially Owned Properties |  |  |  |  |  |  | 0 |  |  | 0
Change in market value of Redeemable Limited Partners |  |  |  |  |  |  | (64,378) |  |  |
Adjustment for Limited Partners ownership in Operating Partnership |  |  |  |  |  |  | 10,607 | (10,607) |  |
LIMITED PARTNERS |  |  |  |  |  |  |  |  |  |
Issuance of restricted units to Limited Partners |  |  |  |  |  |  |  | 3 |  |
Conversion of OP Units held by Limited Partners into OP Units held by General Partner |  |  |  |  |  |  | 4,966 | (4,966) |  |
Conversion of restricted shares to restricted units |  |  |  |  |  |  | (70) | 70 |  |
Equity compensation associated with Units – Limited Partners |  |  |  |  |  |  |  | 21,503 |  |
Net income available to Units – Limited Partners |  |  | 34,241 |  |  |  |  | 34,241 |  |
Units – Limited Partners distributions |  |  |  |  |  |  |  | (31,604) |  |
Change in carrying value of Redeemable Limited Partners |  |  |  |  |  |  |  | (1,672) |  |
Adjustment for Limited Partners ownership in Operating Partnership |  |  |  |  |  |  | 10,607 | (10,607) |  |
Accumulated other comprehensive income (loss) – derivative instruments: |  |  |  |  |  |  |  |  |  |
Unrealized holding gains (losses) arising during the year | 2,219 |  | 2,219 |  |  |  |  |  | 2,219 |
Losses reclassified into earnings from other comprehensive income | (18,244) |  | (18,244) |  |  |  |  |  | 18,244 |
Accumulated other comprehensive income (loss) – other instruments: |  |  |  |  |  |  |  |  |  |
Unrealized holding gains arising during the year | 0 |  | 0 |  |  |  |  |  | 0 |
(Gains) on Sale of Securities, Net |  |  |  |  |  |  |  |  | 0 |
Currency translation adjustments arising during the year | (327) |  | (327) |  |  |  |  |  | (327) |
PARTIALLY OWNED PROPERTIES |  |  |  |  |  |  |  |  |  |
Net income (loss) attributable to Noncontrolling Interests | 908,018 |  | 908,018 |  |  |  |  |  |  | 3,657
Contributions by Noncontrolling Interests | $ 0 |  | $ 0 |  |  |  |  |  |  | 0
Distributions to Noncontrolling Interests |  |  |  |  |  |  |  |  |  | (6,608)
Acquisition of Archstone |  |  |  |  |  |  |  |  |  | 0
Acquisition of Noncontrolling Interests – Partially Owned Properties |  |  |  |  |  |  | 0 |  |  | 0
Deconsolidation of previously consolidated Noncontrolling Interests |  |  |  |  |  |  |  |  |  | (117,350)
Other |  |  |  |  |  |  |  |  |  | 0
Balance, end of period at Dec. 31, 2015 |  |  |  |  | $ 37,280 |  | $ 10,585,104 | $ 221,379 | $ (152,016) | $ 4,608

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