CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Allowance for doubtful accounts	$ 11,554	$ 6,737
Accumulated amortization, deferred leasing costs and intangibles	1,355,013	1,016,989
Accumulated amortization, below market leases	$ 242,422	$ 219,654
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	110,000,000	110,000,000
Preferred stock, shares issued (in shares)	50,650,000	50,650,000
Preferred stock, shares outstanding (in shares)	50,650,000	50,650,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	315,000,000	315,000,000
Common stock, shares issued (in shares)	206,425,656	205,470,300
Common stock, shares outstanding (in shares)	206,425,656	205,470,300
Liquidation preference	$ 1,266,250	$ 1,266,250
Preferred stock, liquidation preference per share (in dollars per share)	$ 25.00	$ 25.00
Acquired above-market leases
Accumulated amortization, acquired above market leases	$ 158,037	$ 110,139
Digital Realty Trust, L.P.
Allowance for doubtful accounts	11,554	6,737
Accumulated amortization, deferred leasing costs and intangibles	1,355,013	1,016,989
Accumulated amortization, below market leases	$ 242,422	$ 219,654
Preferred units, issued (in units)	50,650,000,000	50,650,000,000
Preferred units, outstanding (in units)	50,650,000,000	50,650,000,000
Limited Partners, units outstanding (in units)	10,580,884	8,489,095
Common units, issued (in units)	206,425,656	205,470,300
Common units, outstanding (in units)	206,425,656	205,470,300
Digital Realty Trust, L.P. | Acquired above-market leases
Accumulated amortization, acquired above market leases	$ 158,037	$ 110,139