Pension Plans and Other Postretirement Benefits (Details 7) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Defined Benefit Plan [Member]
Summary of minimum funding requirement and the expected full year contributions for the Company's plans
Minimum funding requirement for 2014	$ 0
Expected contributions (approximations) for the year ended December 31, 2014 as of the time of this Form 10-K (1)	2,000	[1]
Supplemental Retirement Plans [Member]
Summary of minimum funding requirement and the expected full year contributions for the Company's plans
Expected contributions (approximations) for the year ended December 31, 2014 as of the time of this Form 10-K (1)	1,320	[1]
Other Postretirement Benefit [Member]
Summary of minimum funding requirement and the expected full year contributions for the Company's plans
Expected contributions (approximations) for the year ended December 31, 2014 as of the time of this Form 10-K (1)	$ 217	[1]

[1] HMEC’s Annual Report on Form 10-K for the year ended December 31, 2013.