Financial Instruments And Investments (Marketable Securities Fair Value And Unrealized Losses) (Details)
$ in Thousands |
9 Months Ended |
12 Months Ended |
|
Sep. 30, 2016
USD ($)
securities
|
Dec. 31, 2015
USD ($)
securities
|
| Financial Instruments and Investments [Line Items] |
|
|
|
|
| Marketable Securities Fair Value Less than 12 Months |
$ 42,068
|
[1] |
$ 73,859
|
[2] |
| Marketable Securities Unrealized Losses Less Than 12 Months |
(626)
|
[1] |
(2,401)
|
[2] |
| Marketable Securities Fair Value 12 Months or Longer |
22,852
|
[1] |
25,080
|
[2] |
| Marketable Securities Unrealized Losses 12 Months or Longer |
(1,179)
|
[1] |
(1,344)
|
[2] |
| Marketable Securities Fair Value Total |
64,920
|
[1] |
98,939
|
[2] |
| Marketable Securities Unrealized Losses Total |
$ (1,805)
|
[1] |
$ (3,745)
|
[2] |
| Number of securities | securities |
104
|
|
133
|
|
| Debt Securities |
|
|
|
|
| Financial Instruments and Investments [Line Items] |
|
|
|
|
| Marketable Securities Fair Value Less than 12 Months |
$ 17,828
|
[1] |
$ 47,821
|
[2] |
| Marketable Securities Unrealized Losses Less Than 12 Months |
(253)
|
[1] |
(1,289)
|
[2] |
| Marketable Securities Fair Value 12 Months or Longer |
22,852
|
[1] |
25,080
|
[2] |
| Marketable Securities Unrealized Losses 12 Months or Longer |
(1,179)
|
[1] |
(1,344)
|
[2] |
| Marketable Securities Fair Value Total |
40,680
|
[1] |
72,901
|
[2] |
| Marketable Securities Unrealized Losses Total |
(1,432)
|
[1] |
(2,633)
|
[2] |
| Collateralized Mortgage Backed Securities |
|
|
|
|
| Financial Instruments and Investments [Line Items] |
|
|
|
|
| Marketable Securities Fair Value Less than 12 Months |
1,028
|
[1] |
9,383
|
[2] |
| Marketable Securities Unrealized Losses Less Than 12 Months |
(9)
|
[1] |
(97)
|
[2] |
| Marketable Securities Fair Value 12 Months or Longer |
0
|
[1] |
1,113
|
[2] |
| Marketable Securities Unrealized Losses 12 Months or Longer |
0
|
[1] |
(47)
|
[2] |
| Marketable Securities Fair Value Total |
1,028
|
[1] |
10,496
|
[2] |
| Marketable Securities Unrealized Losses Total |
(9)
|
[1] |
(144)
|
[2] |
| U.S. Government Bonds |
|
|
|
|
| Financial Instruments and Investments [Line Items] |
|
|
|
|
| Marketable Securities Fair Value Less than 12 Months |
8,728
|
[1] |
24,094
|
[2] |
| Marketable Securities Unrealized Losses Less Than 12 Months |
(151)
|
[1] |
(310)
|
[2] |
| Marketable Securities Fair Value 12 Months or Longer |
12,300
|
[1] |
14,272
|
[2] |
| Marketable Securities Unrealized Losses 12 Months or Longer |
(526)
|
[1] |
(623)
|
[2] |
| Marketable Securities Fair Value Total |
21,028
|
[1] |
38,366
|
[2] |
| Marketable Securities Unrealized Losses Total |
(677)
|
[1] |
(933)
|
[2] |
| Municipal Bonds |
|
|
|
|
| Financial Instruments and Investments [Line Items] |
|
|
|
|
| Marketable Securities Fair Value Less than 12 Months |
4,692
|
[1] |
8,286
|
[2] |
| Marketable Securities Unrealized Losses Less Than 12 Months |
(43)
|
[1] |
(160)
|
[2] |
| Marketable Securities Fair Value 12 Months or Longer |
8,171
|
[1] |
7,388
|
[2] |
| Marketable Securities Unrealized Losses 12 Months or Longer |
(515)
|
[1] |
(446)
|
[2] |
| Marketable Securities Fair Value Total |
12,863
|
[1] |
15,674
|
[2] |
| Marketable Securities Unrealized Losses Total |
(558)
|
[1] |
(606)
|
[2] |
| Corporate Debt Securities |
|
|
|
|
| Financial Instruments and Investments [Line Items] |
|
|
|
|
| Marketable Securities Fair Value Less than 12 Months |
3,380
|
[1] |
6,058
|
[2] |
| Marketable Securities Unrealized Losses Less Than 12 Months |
(50)
|
[1] |
(722)
|
[2] |
| Marketable Securities Fair Value 12 Months or Longer |
2,381
|
[1] |
2,307
|
[2] |
| Marketable Securities Unrealized Losses 12 Months or Longer |
(138)
|
[1] |
(228)
|
[2] |
| Marketable Securities Fair Value Total |
5,761
|
[1] |
8,365
|
[2] |
| Marketable Securities Unrealized Losses Total |
(188)
|
[1] |
(950)
|
[2] |
| Equity Securities |
|
|
|
|
| Financial Instruments and Investments [Line Items] |
|
|
|
|
| Marketable Securities Fair Value Less than 12 Months |
1,393
|
[1] |
3,584
|
[2] |
| Marketable Securities Unrealized Losses Less Than 12 Months |
(124)
|
[1] |
(344)
|
[2] |
| Marketable Securities Fair Value 12 Months or Longer |
0
|
[1] |
0
|
[2] |
| Marketable Securities Unrealized Losses 12 Months or Longer |
0
|
[1] |
0
|
[2] |
| Marketable Securities Fair Value Total |
1,393
|
[1] |
3,584
|
[2] |
| Marketable Securities Unrealized Losses Total |
(124)
|
[1] |
(344)
|
[2] |
| Institutional Funds-International Equity |
|
|
|
|
| Financial Instruments and Investments [Line Items] |
|
|
|
|
| Marketable Securities Fair Value Less than 12 Months |
22,847
|
[1] |
22,454
|
[2] |
| Marketable Securities Unrealized Losses Less Than 12 Months |
(249)
|
[1] |
(768)
|
[2] |
| Marketable Securities Fair Value 12 Months or Longer |
0
|
[1] |
0
|
[2] |
| Marketable Securities Unrealized Losses 12 Months or Longer |
0
|
[1] |
0
|
[2] |
| Marketable Securities Fair Value Total |
22,847
|
[1] |
22,454
|
[2] |
| Marketable Securities Unrealized Losses Total |
$ (249)
|
[1] |
$ (768)
|
[2] |
|
|