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v3.19.1

MAALP Capital (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018 | Dec. 31, 2017
General Partners' Capital Account [Member] |  |  |  |
Increase (Decrease) in Partners' Capital [Roll Forward] |  |  |  |
Units Issued During Period, Value, Unit Options Exercised |  | $ 625 |  |
Total Partnership Capital [Member] |  |  |  |
Increase (Decrease) in Partners' Capital [Roll Forward] |  |  |  |
Units Issued During Period, Value, Unit Options Exercised | $ 208 | $ 625 |  |
Limited Partner [Member] |  |  |  |
Capital Disclosure [Line Items] |  |  |  |
Distribution Made to Limited Partner, Distributions Declared, Per Unit | $ 0.9600 | $ 0.9225 |  |
Noncontrolling Interest in Joint Ventures | $ 5,166 | $ 2,306 | $ 2,306 | $ 2,306
Increase (Decrease) in Partners' Capital [Roll Forward] |  |  |  |
Dividends, Preferred Stock, Cash | 922 | 922 |  |
Other Noncontrolling Interests | 2,860 |  |  |
Limited Partner [Member] | General Partners' Capital Account [Member] |  |  |  |
Increase (Decrease) in Partners' Capital [Roll Forward] |  |  |  |
Beginning Balance | 6,083,142 | 6,270,758 | 6,270,758 |
Net Income Allocated to General Partners | 62,738 | 48,097 |  |
Issuance of units | 1,129 | 105 |  |
Units repurchased and retired | (3,023) | (2,912) |  |
Units Issued During Period, Value, Unit Options Exercised | 208 |  |  |
General partner units issued in exchange for limited partner units | 336 | 2,780 |  |
Units issued in exchange for redeemable units |  | 1,915 |  |
Redeemable stock fair market value | (1,351) | 965 |  |
Adjustment for noncontrolling interest ownership in operating partnership | 53 | 63 |  |
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification |  | (233) |  |
Amortization of unearned compensation | 4,785 | 4,024 |  |
Distributions | (109,392) | (104,971) |  |
Ending Balance | 6,038,625 | 6,221,216 | 6,083,142 |
Limited Partner [Member] | Total Partnership Capital [Member] |  |  |  |
Increase (Decrease) in Partners' Capital [Roll Forward] |  |  |  |
Beginning Balance | 6,372,170 | 6,573,875 | 6,573,875 |
Net Income Available for Common Unitholders | 65,958 | 50,820 |  |
Other comprehensive (loss) income - derivatives insturments (cash flow hedges) | (3,201) | 639 |  |
Issuance of units | 1,129 | 105 |  |
Units repurchased and retired | (3,023) | (2,912) |  |
General partner units issued in exchange for limited partner units | 0 | 0 |  |
Units issued in exchange for redeemable units |  | 1,915 |  |
Redeemable stock fair market value | (1,351) | 965 |  |
Adjustment for noncontrolling interest ownership in operating partnership | 0 | 0 |  |
Amortization of unearned compensation | 4,785 | 4,024 |  |
Dividends, Preferred Stock, Cash | 922 | 922 |  |
Distributions | (113,333) | (108,790) |  |
Ending Balance | 6,325,280 | 6,520,344 | 6,372,170 |
Limited Partner [Member] | Limited Partner [Member] |  |  |  |
Capital Disclosure [Line Items] |  |  |  |
Noncontrolling Interest in Joint Ventures | 2,860 |  |  |
Increase (Decrease) in Partners' Capital [Roll Forward] |  |  |  |
Beginning Balance | 220,043 | 231,676 | 231,676 |
Net Income Allocated to Limited Partners | 2,298 | 1,801 |  |
General partner units issued in exchange for limited partner units | (336) | (2,780) |  |
Adjustment for noncontrolling interest ownership in operating partnership | (53) | (63) |  |
Distributions | (3,941) | (3,819) |  |
Ending Balance | 218,011 | 226,815 | 220,043 |
Limited Partner [Member] | AOCI Attributable to Noncontrolling Interest [Member] |  |  |  |
Increase (Decrease) in Partners' Capital [Roll Forward] |  |  |  |
Beginning Balance | (161) | 2,295 | 2,295 |
Other comprehensive (loss) income - derivatives insturments (cash flow hedges) | (3,201) | 639 |  |
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification |  | 233 |  |
Ending Balance | (3,362) | 3,167 | (161) |
Accumulated Distributions in Excess of Net Income [Member] | Limited Partner [Member] |  |  |  |
Increase (Decrease) in Partners' Capital [Roll Forward] |  |  |  |
Issuance of units | 0 | 0 | $ 66,840 |
Dividends, Preferred Stock, Cash | 922 | 922 |  |
Preferred Stock Including Additional Paid in Capital [Member] | Limited Partner [Member] |  |  |  |
Increase (Decrease) in Partners' Capital [Roll Forward] |  |  |  |
Ending Balance | $ 66,840 | $ 66,840 |  |

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