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CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (Unaudited) - 6 months ended Jun. 30, 2017 - USD ($) $ in Thousands | Total | PREFERRED SHARES | COMMON SHARES, $0.01 PAR VALUE | PAID IN CAPITAL | RETAINED EARNINGS | ACCUMULATED OTHER COMPREHENSIVE (LOSS) | OPERATING PARTNERSHIP | PARTIALLY OWNED PROPERTIES
--- | --- | --- | --- | --- | --- | --- | --- | ---
Balance, beginning of year at Dec. 31, 2016 | $ 10,229,078 | $ 37,280 | $ 3,659 | $ 8,758,422 | $ 1,543,626 | $ (113,909) |  |
Balance, beginning of year at Dec. 31, 2016 | 231,906 |  |  |  |  |  | $ 221,297 | $ 10,609
COMMON SHARES, $0.01 PAR VALUE |  |  |  |  |  |  |  |
Conversion of OP Units into Common Shares |  |  | 11 | 14,611 |  |  | (14,622) |
Exercise of share options |  |  | 2 | 8,141 |  |  |  |
Restricted shares |  |  | 1 | 5,381 |  |  |  |
Share options |  |  |  | 5,979 |  |  |  |
ESPP discount |  |  |  | 414 |  |  |  |
PAID IN CAPITAL |  |  |  |  |  |  |  |
Conversion of OP Units into Common Shares |  |  | 11 | 14,611 |  |  | (14,622) |
Exercise of share options |  |  | 2 | 8,141 |  |  |  |
Employee Share Purchase Plan (ESPP) |  |  |  | 2,111 |  |  |  |
Share-based employee compensation expense |  |  |  |  |  |  |  |
Offering costs |  |  |  | (36) |  |  |  |
Supplemental Executive Retirement Plan (SERP) |  |  |  | (666) |  |  |  |
Change in market value of Redeemable Noncontrolling Interests – Operating Partnership | (30,351) |  |  | 30,351 |  |  |  |
Adjustment for Noncontrolling Interests ownership in Operating Partnership |  |  |  | 14,096 |  |  | (14,096) |
RETAINED EARNINGS |  |  |  |  |  |  |  |
Net income attributable to controlling interests | 339,783 |  |  |  | 339,783 |  |  |
Common Share distributions |  |  |  |  | (369,964) |  |  |
Preferred Share distributions |  |  |  |  | (1,546) |  |  |
Accumulated other comprehensive income – derivative instruments: |  |  |  |  |  |  |  |
Unrealized holding gains (losses) arising during the period | 3,507 |  |  |  |  | 3,507 |  |
Losses reclassified into earnings from other comprehensive income | (9,251) |  |  |  |  | 9,251 |  |
OPERATING PARTNERSHIP |  |  |  |  |  |  |  |
Conversion of OP Units into Common Shares |  |  | 11 | 14,611 |  |  | (14,622) |
Equity compensation associated with Noncontrolling Interests |  |  |  |  |  |  | 5,869 |
Net income | 354,101 |  |  |  |  |  |  |
Distributions to Noncontrolling Interests |  |  |  |  |  |  | (13,386) | (5,984)
Change in carrying value of Redeemable Noncontrolling Interests – Operating Partnership | (31,222) |  |  |  |  |  | 31,222 |
Adjustment for Noncontrolling Interests ownership in Operating Partnership |  |  |  | 14,096 |  |  | (14,096) |
Net income attributable to Noncontrolling Interests | 12,765 |  |  |  |  |  | 12,765 | 1,553
PARTIALLY OWNED PROPERTIES |  |  |  |  |  |  |  |
Net income | 354,101 |  |  |  |  |  |  |
Distributions to Noncontrolling Interests |  |  |  |  |  |  | (13,386) | (5,984)
Net income attributable to Noncontrolling Interests | 12,765 |  |  |  |  |  | 12,765 | 1,553
Contributions – Noncontrolling Interests – Partially Owned Properties | 125 |  |  |  |  |  |  | 125
Balance, end of period at Jun. 30, 2017 | 10,290,505 | $ 37,280 | $ 3,673 | $ 8,838,804 | $ 1,511,899 | $ (101,151) |  |
Balance, end of period at Jun. 30, 2017 | $ 235,352 |  |  |  |  |  | $ 229,049 | $ 6,303

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