| In millions, except per share items | Dec-31-15 | Dec-31-14 | Dec-31-13 | Dec-31-12 | Dec-31-11 | Dec-31-10 | Dec-31-09 | Dec-31-08 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Cash flows from operating activities: | | | | | | | | |
| Net income | 25.5 | 39.1 | 111.7 | 17.7 | -7.1 | 1.5 | | |
| Adjustments to reconcile net income to net cash from operating activities: | | | | | | | | |
| Provision for asset impairment | | | | | | | | |
| Depreciation and amortization | 68.4 | 72.0 | 70.5 | 56.1 | 51.0 | 45.5 | | |
| Amortization of deferred stock compensation | 0.8 | -0.8 | -0.7 | -0.7 | -0.1 | 0.0 | | |
| Amortization on acquired above/below market leases and lease inducements | 0.0 | 0.3 | 0.3 | -0.5 | -0.3 | 0.2 | | |
| Gain on sale of investment properties | -12.0 | -25.4 | -11.6 | -3.4 | -1.5 | -1.9 | | |
| Gain from change in control of investment properties | | | -95.4 | -1.1 | | | | |
| Impairment of investment securities | | | | | | | | |
| Gain from settlement of receivables | | | | | | | | |
| Realized gain on investment securities, net | | | -1.0 | -1.4 | -1.3 | -2.4 | | |
| Equity in earnings of unconsolidated ventures | -10.8 | -8.8 | -7.9 | -2.9 | 8.1 | 4.4 | | |
| Gain on sale of joint venture interest | | | -1.0 | -1.4 | -1.3 | -2.4 | | |
| Straight line rent | -0.7 | -1.5 | -1.3 | -0.9 | -1.6 | -1.6 | | |
| Amortization of loan fees | 2.0 | 2.9 | 1.6 | 3.0 | 3.7 | 2.4 | | |
| Amortization of debt premium/discount, net | -0.4 | -0.6 | -0.3 | 0.5 | 1.3 | 1.4 | | |
| Distributions from unconsolidated joint ventures | 5.3 | | | 0.4 | 1.1 | 0.9 | | |
| Changes in assets and liabilities: | | | | | | | | |
| Restricted cash | | 0.1 | 0.1 | 1.3 | 1.4 | -0.4 | | |
| Accounts receivable and other assets, net | 1.1 | 7.1 | 0.1 | -10.3 | 6.4 | 3.1 | | |
| Accounts payable and accrued expenses | 7.7 | 2.1 | -7.6 | 10.7 | -2.7 | 2.9 | | |
| Prepaid rents and other liabilities | 0.3 | -3.2 | -1.2 | 0.4 | -3.3 | -3.2 | | |
| Net cash provided by operating activities | 97.4 | 82.5 | 69.0 | 69.0 | 63.3 | 59.5 | | |
| |
| Cash flows from investing activities: | | | | | | | | |
| Restricted cash | -5.6 | -3.0 | -4.9 | 2.4 | 0.0 | -2.6 | | |
| Proceeds from sale of interest in joint venture, net | 10.3 | 46.1 | 71.6 | 29.9 | 62.9 | 35.5 | | |
| Sale of investment securities | | | 7.8 | 7.3 | 2.6 | 4.7 | | |
| Purchase of investment properties | -53.1 | -112.7 | -191.6 | -242.7 | -125.6 | -102.5 | | |
| Additions to investment properties, net of accrued additions | -69.9 | -30.4 | -20.5 | -24.4 | -40.8 | -23.5 | | |
| Proceeds from sale of investment properties and land condemnations, net | 58.5 | 60.3 | 47.6 | | | | | |
| Distributions from unconsolidated joint ventures | 32.2 | 15.2 | 15.1 | 34.9 | 8.8 | 10.4 | | |
| Investment in unconsolidated joint ventures | -27.6 | -56.8 | -36.4 | -15.4 | -11.1 | -4.8 | | |
| Funding of mortgages and notes receivable | | -24.8 | -1.3 | -13.0 | | | | |
| Repayments of mortgages and notes receivable | 24.8 | | | | | | | |
| Payment of leasing fees | -2.9 | -2.6 | -3.0 | -3.2 | -4.4 | -2.8 | | |
| Net cash used in investing activities | -33.3 | -108.6 | -115.7 | -182.6 | -101.9 | -28.7 | | |
| |
| Cash flows from financing activities: | | | | | | | | |
| Issuance of shares, net of offering costs | 4.4 | 100.9 | 104.5 | 61.6 | | | | |
| Purchase of noncontrolling interest, net | 1.4 | 0.6 | -8.5 | 0.1 | -0.7 | -1.2 | | |
| Loan proceeds | 113.9 | 356.7 | 181.8 | 346.9 | 374.7 | 384.5 | | |
| Payoff of debt | -10.6 | -110.2 | -33.6 | -36.6 | -66.4 | -179.8 | | |
| Proceeds from term loan | | 20.0 | 5.0 | 25.0 | 50.0 | 10.0 | | |
| Proceeds from the unsecured line of credit facility | 82.0 | 307.0 | 155.0 | 177.0 | 231.4 | 187.0 | | |
| Repayments on the unsecured line of credit facility | -107.0 | -212.0 | -140.0 | -177.0 | -196.4 | -187.0 | | |
| Repayments on convertible notes | | -32.5 | | | -82.6 | -15.5 | | |
| Loan fees | -0.3 | -2.0 | -0.3 | -3.1 | -3.2 | -7.3 | | |
| Distributions paid | -73.2 | -67.0 | -62.9 | -58.5 | -51.3 | -48.9 | | |
| Distributions to noncontrolling interest | | | -0.4 | -7.4 | -0.6 | -0.7 | | |
| Contributions from noncontrolling interest | 1.4 | 0.6 | -8.5 | 0.1 | -0.7 | -1.2 | | |
| Payment of earnout liability | -1.5 | -1.2 | -1.2 | | | | | |
| Net cash provided by (used in) financing activities | -72.9 | 33.3 | 39.4 | 124.4 | 32.8 | -23.9 | | |
| Net increase (decrease) in cash and cash equivalents | -8.9 | 7.1 | -7.2 | 10.8 | -5.8 | 6.8 | | |
| Cash and cash equivalents at beginning of year | 18.4 | 11.3 | 18.5 | 7.8 | 13.6 | 6.7 | | |
| Cash and cash equivalents at end of year | 9.5 | 18.4 | 11.3 | 18.5 | 7.8 | 13.6 | | |
| |
| Supplemental disclosure of cash flow information | | | | | | | | |
| Cash paid for interest, net of capitalized interest | 22.5 | 27.5 | 26.1 | 27.5 | 36.5 | 30.1 | | |
| Non-cash accrued additions to investment properties | -1.5 | 2.2 | -1.5 | 2.0 | -3.5 | -1.0 | | |
| Non-cash distributions to noncontrolling interests | | 0.0 | -9.4 | -9.1 | | | | |
| Non-cash contributions from noncontrolling interests | | | 7.1 | 9.1 | | | | |