CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 14,074	$ 3,191
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	32,210	31,408
Amortization of above/below market leases	(431)	(797)
Amortization of deferred financing costs	847	872
Amortization of share-based compensation	3,578	2,526
Bad debt expense	157	36
Changes in operating assets and liabilities:
Accounts receivable	1,814	(1,478)
Deferred rent receivable	(618)	(2,477)
Deferred leasing costs	(4,204)	(2,544)
Other assets	(1,025)	(1,196)
Accounts payable and accrued expenses	(2,215)	(246)
Prepaid rent and other liabilities	273	(1,989)
Deferred rent payable	1,395	492
Net cash provided by operating activities	45,855	27,798
CASH FLOWS FROM INVESTING ACTIVITIES
Tenant improvements	(3,405)	(3,417)
Real estate improvements	(68,161)	(31,800)
Acquisition of NY2	(21,889)
Acquisition of Comfluent, net of cash received		(2,581)
Changes in reserves for capital improvements		153
Net cash used in investing activities	(93,455)	(37,645)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from exercise of stock options	525	795
Proceeds from revolving credit facility	73,000	49,750
Principal payments on mortgage loans	(750)	(25,165)
Payments of loan fees and costs	(2,617)	(106)
Dividends and distributions paid on common stock and OP units	(25,033)	(16,529)
Dividends paid on preferred stock	(2,852)
Net cash provided by financing activities	42,273	8,745
Net change in cash and cash equivalents	(5,327)	(1,102)
Cash and cash equivalents, beginning of period	8,130	6,628
Cash and cash equivalents, end of period	2,803	5,526
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash paid for interest	1,860	2,974
NON-CASH INVESTING AND FINANCING ACTIVITY
Construction costs payable capitalized to real estate	12,708	6,380
Accrual of dividends and distributions	$ 14,902	$ 8,580