Fair Value Measurement (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value Measurement [Abstract]

Fair Value Assets Recurring and Nonrecurring

		June 30, 2017					December 31, 2016
	Category		Carrying amount		Fair value		Carrying amount		Fair value
Fair values disclosed, recurring:
Cash and cash equivalents	Level 1	$	254,103	$	254,103	$	207,867	$	207,867
Restricted cash	Level 1		113,391		113,391		550,222		550,222
Short-term debt (note 18)	Level 2		14,110		14,110		23,912		23,912
Long-term debt (note 18)
Senior unsecured notes	Level 1		486,495		522,500		495,780		509,500
Revolving loans	Level 2		-		-		99,926		99,926
Delayed draw term loans	Level 2		327,818		332,363		-		-