Note 15 - Commitments and Contingencies	3 Months Ended
Jun. 30, 2019
Notes to Financial Statements
Commitments and Contingencies Disclosure [Text Block]	15. Commitments and Contingencies Legal Contingencies From time to time, the Company is involved in legal and administrative proceedings and claims of various types. The Company records a liability in its consolidated financial statements for these matters when a loss is known or considered probable and the amount can be reasonably estimated. The Company reviews these estimates each accounting period as additional information is known and adjusts the loss provision when appropriate. If a matter is both probable to result in a liability and the amounts of loss can be reasonably estimated, the Company estimates and discloses the possible loss or range of loss to the extent necessary to make the consolidated financial statements not misleading. If the loss is not probable or cannot be reasonably estimated, a liability is not recorded in its consolidated financial statements. Other The Company enters into long-term construction contracts with customers that require the Company to obtain performance bonds. The Company is required to deposit an amount equivalent to some or all the face amount of the performance bonds into an escrow account until the termination of the bond. When the performance conditions are met, amounts deposited as collateral for the performance bonds are returned to the Company. In addition, the Company has various contractual arrangements in which minimum quantities of goods or services have been committed to be purchased on an annual basis. As of June 30, 2019 , the Company had $ 0.7 million of restricted cash included in long-term assets. These amounts included in restricted cash primarily represent deposits to secure letters of credit for various supply contracts. These deposits are held in interest bearing accounts. As part of the agreement with Commonwealth Edison Company to install the Resilient Electric Grid ("REG") system in Chicago, the Company agreed to deliver an irrevocable letter of credit in the amount of $5.0 million to secure certain Company obligations under the Subcontract Agreement. The funds to secure the $5.0 million letter of credit were deposited in an escrow account on July 1, 2019.

15.

Commitments and Contingencies

Legal Contingencies

From time to time, the Company is involved in legal and administrative proceedings and claims of various types. The Company records a liability in its consolidated financial statements for these matters when a loss is known or considered probable and the amount can be reasonably estimated. The Company reviews these estimates each accounting period as additional information is known and adjusts the loss provision when appropriate. If a matter is both probable to result in a liability and the amounts of loss can be reasonably estimated, the Company estimates and discloses the possible loss or range of loss to the extent necessary to make the consolidated financial statements

not

misleading. If the loss is

not

probable or cannot be reasonably estimated, a liability is

not

recorded in its consolidated financial statements.

Other

The Company enters into long-term construction contracts with customers that require the Company to obtain performance bonds. The Company is required to deposit an amount equivalent to some or all the face amount of the performance bonds into an escrow account until the termination of the bond. When the performance conditions are met, amounts deposited as collateral for the performance bonds are returned to the Company. In addition, the Company has various contractual arrangements in which minimum quantities of goods or services have been committed to be purchased on an annual basis.

As of

June 30, 2019

, the Company had $

0.7

million of restricted cash included in long-term assets. These amounts included in restricted cash primarily represent deposits to secure letters of credit for various supply contracts. These deposits are held in interest bearing accounts. As part of the agreement with Commonwealth Edison Company to install the Resilient Electric Grid ("REG") system in Chicago, the Company agreed to deliver an irrevocable letter of credit in the amount of

$5.0

million to secure certain Company obligations under the Subcontract Agreement. The funds to secure the

$5.0

million letter of credit were deposited in an escrow account on

July 1, 2019.