The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Dividends received on equity and other investments during the current period.

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Note 9 - Equity Method Investments (Details Textual) - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Aug. 31, 2016	Feb. 29, 2016
Income (Loss) from Equity Method Investments	$ 887	$ (405)
Due from Related Parties, Current	3,928		$ 3,447
Costamare Ventures [Member]
Due from Related Parties, Current	0		0
Kemp Maritime Co. and Hyde Maritime Co. [Member]
Line of Credit Facility, Maximum Borrowing Capacity	88,000	$ 88,000
Ainsley Maritime Co. and Ambrose Maritime Co. [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 86,600				$ 86,600
Steadman Maritime Co. [Member]
Equity Method Investment, Ownership Percentage	49.00%
Steadman Maritime Co. [Member] \| Costamare Ventures [Member]
Payments to Acquire Equity Method Investments	$ 693		613
Horton Maritime Co. [Member]
Equity Method Investment, Ownership Percentage	49.00%
Proceeds from Dividends Received	$ 270		613
Kemp Maritime Co. and Hyde Maritime Co. [Member] \| Costamare Ventures [Member]
Payments to Acquire Equity Method Investments	3,130
Ainsley Maritime Co. and Ambrose Maritime Co. [Member] \| Costamare Ventures [Member]
Payments to Acquire Equity Method Investments	$ 498		4,662
Benedict, Bertrand, Beardmore, Schofield, and Fairbank Maritime Co. [Member] \| Costamare Ventures [Member]
Payments to Acquire Equity Method Investments			25,323
Smales Maritime Co. [Member]
Equity Method Investment, Ownership Percentage	49.00%
Smales Maritime Co. [Member] \| Costamare Ventures [Member]
Payments to Acquire Equity Method Investments			463
Skerrett Maritime Co. [Member]
Equity Method Investment, Ownership Percentage	49.00%
Skerrett Maritime Co. [Member] \| Costamare Ventures [Member]
Payments to Acquire Equity Method Investments	$ 1,278		218
Geyer Maritime Co. [Member]
Equity Method Investment, Ownership Percentage	49.00%
Geyer Maritime Co. [Member] \| Costamare Ventures [Member]
Payments to Acquire Equity Method Investments	$ 798
Goodway Maritime Co. [Member]
Equity Method Investment, Ownership Percentage	49.00%
Goodway Maritime Co. [Member] \| Costamare Ventures [Member]
Equity Method Investment, Ownership Percentage						49.00%
Payments to Acquire Equity Method Investments			2,925	$ 637
Platt Maritime Co. and Sykes Maritime Co. [Member]
Payments to Acquire Equity Method Investments	$ 649		$ 427