Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Fair Value of Derivatives and Financial Instruments (Effect of Derivative Instruments on Consolidated Statement of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Designated as Hedging Instrument \| Interest Expense
Derivative
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	$ (193)	$ 672
Designated as Hedging Instrument \| Interest Rate Contract
Derivative
Unrealized (loss) gain from the effective portion of derivative instruments	832	2,520
Not Designated as Hedging Instrument \| Interest Expense
Derivative
Derivative Instruments, Gain (Loss) Recognized in Income, Net	(2,644)	2,353
Parent Company [Member]
Derivative
Accumulated other comprehensive income (losses)	3,000	4,223	$ 2,157	$ 1,144
Unrealized (loss) gain from the effective portion of derivative instruments	$ 832	$ 2,520