| In millions, except per share items | Mar-31-23 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 | Jun-30-21 | Mar-31-21 | Dec-31-20 |
| | 10-Q | 10-Q | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K |
| Cash flows from operating activities: | | | | | | | | |
| Net income (loss) | 134.5 | 72.3 | 75.3 | 32.6 | 61.9 | 282.0 | 149.4 | 150.2 |
| Adjustments to reconcile net income (loss) to net cash from (used in) operating activities: | | | | | | | | |
| Stock-based compensation amortization expense | 3.3 | 5.3 | 4.7 | 4.3 | 4.4 | 5.1 | 4.4 | 4.0 |
| Amortization of deferred financing costs | 2.8 | 2.7 | 2.7 | 2.5 | 2.3 | 2.1 | 2.2 | 2.5 |
| Straight-line rents | -0.7 | -12.7 | -11.2 | -7.6 | -8.3 | -6.2 | -9.1 | -0.4 |
| Amortization of nonrefundable entrance fees and above (below) market lease intangibles | -25.7 | | -24.7 | | | | | |
| Equity loss (income) from unconsolidated joint ventures | -1.8 | -0.4 | -2.1 | -1.7 | -2.4 | -6.1 | -1.0 | 19.2 |
| Distributions of earnings from unconsolidated joint ventures | 0.2 | 0.2 | 0.2 | 0.2 | 0.7 | 3.8 | 0.2 | 0.4 |
| Loss (gain) on sales of real estate, net | -81.6 | -12.9 | -3.8 | -6.8 | -41.4 | -297.5 | -259.7 | -302.6 |
| Casualty-related loss (recoveries), net | 0.5 | 0.1 | | | 0.6 | 0.2 | 0.9 | |
| Changes in: | | | | | | | | |
| Decrease (increase) in accounts receivable and other assets, net | -19.9 | 14.9 | -4.1 | -9.0 | -5.4 | 21.4 | 11.6 | -7.2 |
| Increase (decrease) in accounts payable, accrued liabilities, and deferred revenue | -15.9 | 31.3 | 3.7 | 39.3 | 24.4 | 18.6 | -74.5 | 65.0 |
| Net cash provided by (used in) operating activities | 173.9 | 255.5 | 194.2 | 223.9 | 211.7 | 236.9 | 122.7 | 218.7 |
| |
| Cash flows from investing activities: | | | | | | | | |
| Acquisitions of real estate | -10.2 | -25.1 | -134.1 | -504.6 | -480.3 | -483.2 | -14.9 | -830.2 |
| Development, redevelopment, and other major improvements of real estate | -204.9 | -188.1 | -178.3 | -180.0 | -148.7 | -146.5 | -135.3 | -214.0 |
| Investments in unconsolidated joint ventures | -9.6 | -0.5 | -1.5 | -12.4 | -2.7 | -4.2 | -5.9 | -29.3 |
| Distributions in excess of earnings from unconsolidated joint ventures | 3.2 | 1.6 | 3.9 | 0.5 | 2.6 | 23.8 | 10.8 | 12.4 |
| Net cash provided by (used in) investing activities | 56.3 | -215.2 | -246.0 | -672.6 | -508.6 | 944.6 | 767.7 | -241.2 |
| |
| Cash flows from financing activities: | | | | | | | | |
| Issuances and borrowings of term loans, senior unsecured notes, and mortgage debt | 399.5 | | | 497.0 | 449.4 | 142.1 | | |
| Payments for debt extinguishment and deferred financing costs | | | | | | | | |
| Issuance of common stock and exercise of options, net of offering costs | -0.2 | 0.0 | 0.0 | 0.3 | 3.5 | 0.1 | 1.1 | 1.2 |
| Repurchase of common stock | -6.5 | -0.3 | -11.4 | -0.3 | -0.1 | -0.3 | -12.2 | -0.3 |
| Dividends paid on common stock | -165.0 | -161.8 | -163.4 | -162.0 | -162.0 | -162.0 | -164.1 | -199.5 |
| Distributions to and purchase of noncontrolling interests | -22.8 | -8.4 | -7.5 | -68.9 | -7.7 | -9.0 | -7.7 | -17.7 |
| Contributions from and issuance of noncontrolling interests | 0.1 | 0.4 | 0.2 | 0.2 | 0.4 | | | |
| Net cash provided by (used in) financing activities | -239.9 | -53.6 | -18.5 | 399.4 | 321.4 | -1,085.2 | -924.1 | -95.3 |