Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Cash Flows From Operating Activities
Net income	$ 7,888	$ 11,231
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	41,418	30,115
Amortization of deferred finance costs and debt premiums and discount	1,220	534
Amortization of acquired above- and below-market leases, net	(5,291)	(1,885)
Amortization of acquired below-market ground leases	1,958	426
Straight-lining of rental revenue	(4,102)	(12,580)
Equity based compensation	1,694	1,025
Increase (decrease) in cash flows due to changes in operating assets and liabilities:
Restricted cash	3,179	(2,777)
Tenant and other receivables	10,986	(4,530)
Deferred leasing costs	(16,396)	(1,372)
Prepaid expenses and other assets	17,789	11,872
Accounts payable and accrued expenses	(6,057)	(9,155)
Deferred revenue and other liabilities	(6,905)	1,006
Net cash provided by operating activities	47,381	23,910
Cash Flows From Investing Activities
Decrease in restricted cash for investing activities	28	5,098
Development costs	(346)	0
Additions to building and improvements	(27,717)	(20,136)
Net cash used in investing activities	(28,035)	(15,038)
Cash Flows From Financing Activities
Repayment of mortgage notes payable	(47,084)	(4,011)
Proceeds from unsecured revolving credit facility	495,000	0
Repayments of unsecured revolving credit facility	(330,000)	0
Proceeds from term loan and credit facility	0	10,000
Repayments of term loan and credit facility	(470,000)	(10,000)
Proceeds from senior unsecured notes	350,000	0
Deferred financing costs and equity issuance costs	(3,558)	0
Private perpetual preferred unit distributions	(234)	0
Dividends paid to common stockholders	(9,406)	(8,128)
Distributions paid to non-controlling interests in the operating partnership	(13,333)	(12,773)
Net cash used in financing activities	(28,615)	(24,912)
Net decrease in cash and cash equivalents	(9,269)	(16,040)
Cash and cash equivalents—beginning of period	45,732	60,743
Cash and cash equivalents—end of period	36,463	44,703
Supplemental disclosures of cash flow information:
Cash paid for interest	15,742	13,811
Cash paid for income taxes	1,434	47
Non-cash investing and financing activities:
Commercial real estate properties included in accounts payable and accrued expenses	47,533	14,138
Conversion of operating partnership units and Class B shares to Class A shares	$ 19,538	$ 0