Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 44,002	$ 101,932
Adjustments to reconcile net income to net cash provided by operating activities (including discontinued operations):
Depreciation and amortization of building and improvements and leasing costs	50,843	48,717
Increase in provision for bad debts	242	0
Depreciation of furniture, fixtures and equipment	644	485
Noncash amortization of share-based compensation awards	3,571	2,502
Noncash amortization of deferred financing costs and debt discounts and premiums	454	1,256
Noncash amortization of net below market rents (Note 4)	(1,928)	(1,734)
Gains on dispositions of discontinued operations	0	(90,115)
Gain on sale of land (Note 3)	(17,268)	0
Noncash amortization of deferred revenue related to tenant-funded tenant improvements	(3,013)	(2,353)
Straight-line rents	(19,692)	(3,959)
Net change in other operating assets	(8,421)	(5,949)
Net change in other operating liabilities	5,545	(5,701)
Net cash provided by operating activities	54,979	45,081
CASH FLOWS FROM INVESTING ACTIVITIES:
Expenditures for acquisition of operating properties	0	(106,125)
Expenditures for operating properties	(24,345)	(32,016)
Expenditures for development and redevelopment properties and undeveloped land	(89,810)	(73,626)
Expenditures for acquisition of development properties (Note 2)	(50,435)	0
Net proceeds received from land and operating properties (Note 3)	25,563	309,824
Decrease (increase) in acquisition-related deposits	3,099	0
Decrease (increase) in restricted cash (Note 1)	58,619	(779)
Net cash (used in) provided by investing activities	(77,309)	97,278
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from issuance of common stock (Note 8)	113,097	0
Borrowings on unsecured line of credit	150,000	90,000
Repayments on unsecured line of credit	(160,000)	(135,000)
Principal payments on secured debt	(28,472)	(2,414)
Financing costs	(397)	(418)
Repurchase of common stock and restricted stock units	(1,821)	(1,517)
Proceeds from exercise of stock options (Note 10)	10,482	21
Dividends and distributions paid to common stockholders and common unitholders	(30,846)	(29,561)
Dividends and distributions paid to preferred stockholders and preferred unitholders	(3,313)	(3,313)
Net cash provided by (used in) financing activities	48,730	(82,202)
Net increase in cash and cash equivalents	26,400	60,157
Cash and cash equivalents, beginning of period	23,781	35,377
Cash and cash equivalents, end of period	50,181	95,534
SUPPLEMENTAL CASH FLOWS INFORMATION:
Cash paid for interest, net of capitalized interest of $10,669 and $10,042 as of March 31, 2015 and 2014, respectively	19,814	14,106
NONCASH INVESTING TRANSACTIONS:
Accrual for expenditures for operating properties and development and redevelopment properties	85,656	64,709
Tenant improvements funded directly by tenants	231	4,470
Assumption of other liabilities in connection with development acquisitions	1,478	0
Release of holdback funds to third party	8,279	0
NONCASH FINANCING TRANSACTIONS:
Accrual of dividends and distributions payable to common stockholders and common unitholders	31,892	29,906
Accrual of dividends and distributions payable to preferred stockholders and preferred unitholders	1,656	1,656
Fair value of share-based compensation awards at equity classification date (Note 10)	16,920	0
Exchange of common units of the Operating Partnership into shares of the Company’s common stock	$ 316	$ 28